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THE PRACTI CE

OF

maki ng; and r epai r i ng ROADS;

OF CONSTRUCTI NG

FOOTPATHS, FENCES, AND DRAI NS;

THE PRACTI CE

MAKI NG Sf REPAI RI NG ROADS ;

OF CONSTRUCTI NG

FOOTPATHS, FENCES, AND DRAI NS;

ALSO,

A METHOD OF COMPARI NG ROADS,

WI TH REFERENCE TO THE POWER OF DRAUGHT REQUI RED:

WLi t f i pr act i cal

! ) ser bat t ons,

I NTENDED TO

SI MPLI FY THE MODE OP ESTI MATI NG EARTHWORK

I N CUTTI NGS AND EMBANKMENTS.

BY THOMAS HUGHES, ESQ.

CJVI L EAGI NEER.

CHAPTER I .

Obser vat i ons on t he necessi t y f or a gener al I mpr ovement

of t he common Roads.

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Whi l e t he i mpor t ant mai n l i nes of r oad t hr oughout

t hi s count r y have ar r i ved at a degr ee of excel l ence

whi ch may j ust l y ent i t l e t hem t o some shar e of admi r a-

t i on, t he gener al condi t i on of our par i sh and ot her

r oads can l eave no doubt of t he f act , t hat t he pr i nci pl es

of r oadmaki ng, si mpl e and easi l y der i vabl e as t hey ar e,

f r om a f ew obvi ous t r ut hs, ar e yet but i mper f ect l y

under st ood by t he sur veyor s and ot her s, under whose

management t hese r oads ar e pl aced.

I f t he pr i nci pl es of r oadmaki ng coul d onl y be appl i ed

wi t h advant age i n t hose cases wher e ampl e f unds ar e at

t he command of t he sur veyor , t hey woul d be compar a-

t i vel y of smal l val ue t o t he sur veyor s of any but t he

gr eat t ur npi ke- r oads. That t he expendi t ur e of gr eat

sums of money, however , becomes a necessar y conse-

quence of t he det er mi nat i on t o obt ai n a super i or r oad,

i s a not i on so er r oneous, so danger ous and pr ej udi ci al

t o t he publ i c i nt er est s, t hat i t cannot be t oo st r ongl y

guar ded agai nst .

I n t he const r uct i on of r oads, as wel l as i n most

ot her wor ks of engi neer i ng, t he gr eat est amount of

cr edi t i s not , as a mat t er of cour se, due t o hi m who

pr oduces t he best ki nd of r oad ; because, however excel -

l ent t he pr oduct i on may be, i t i s possi bl e t hat i t s cost

may have been so enor mous, t hat , bal anci ng on t he one

B

hand t he advant age of a good r oad agai nst t he out l ay of

a di spr opor t i onat el y vast sur a of money, t he engi neer

af t er al l , i nst ead of conf er r i ng a boon upon t he count r y,

may have i nf l i ct ed a ser i ous evi l . Thi s may be con-

si der ed an ext r eme case, but onl y because we r ar el y

f i nd t hat t r ust ees ar e di sposed t o compl ai n of t hei r

engi neer or sur veyor f or havi ng expended t oo much

money, pr ovi ded he succeed i n const r uct i ng a ver y

super i or r oad. But , not wi t hst andi ng t hi s gener osi t y of

f eel i ng, we may r eadi l y suppose t hat t he par t i es Avho

bear t he expense of const r uct i ng t he r oad, woul d be at

l east as wel l pl eased t o obt ai n t he same ki nd of r oad

at a consi der abl e di mi nut i on of cost . The necessi t y

of economy i n t he const r uct i on of r oads, wi t hout at

t he same t i me sacr i f i ci ng t hat excel l ence whi ch ought

t o f or m a pr i mar y consi der at i on, i s, per haps, mor e

ur gent now t han at any f or mer per i od i n t he hi st or y of

t hi s count r y. The vast and over whel mi ng compet i t i on

of t he r ai l way syst em, t hr eat ens t o t hr ow i nt o t he shade

our ver y best t ur npi ke- r oads ; but , at t he same t i me,

i t r equi r es no ver y pr of ound j udgment t o di scover ,

t hat t he common r oads wi l l possess a much bet t er

) chance of compet i t i on wi t h t he r ai l r oads, i f t he f or mer

coul d be i mpr oved t o any consi der abl e ext ent , wi t hout

\ at t he same t i me i ncr easi ng t he expenses of mai nt enance

I and of t r avel l i ng over t hem.

/ / The pr esent condi t i on of our common r oad syst em

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' ^ appear s t o cal l f or some i mpr ovement , wi t h a degr ee of

ear nest ness not unwor t hy t he at t ent i on of an enl i ght ened

Gover nment . I t has now became a quest i on f or t hei r

ser i ous consi der at i on, whet her t he exi st i ng r oads ar e

t o be ent i r el y suppl ant ed, and t he vast sums of money

expended upon t hem t o be sacr i f i ced, wi t hout one cf i br t

t o save t hem f r om t he i nsat i abl e r apaci t y of t he al l -

devour i ng r ai l ways. I s i t not enough t o al ar m ever y

one i nt er est ed i n t he wel f ar e of our anci ent r oads, t o

r ef l ect , t hat t he l east boast i ndul ged i n by ever y one of

t he whol e host of r ai l ways i s, mer el y, t hat al l t he t r af f i c

of al l t he r oads i n i t s own di r ect i on, wi l l at once and

i mmedi at el y f or sake t he ol d accust omed r out e, and di s -

dai ni ng t he humbl e paces of ei ght or t en mi l es an hour ,

wi l l f l ock t o t he r ai l way st at i ons, t o enj oy t he i nest i -

mabl e sat i sf act i on of bei ng whi r l ed al ong at t he r at e of

t went y or t hi r t y mi l es an hour !

At t he same t i me, however , t hat t he compl acent

pr et ensi ons of r ai l way compani es, as we see t hem

advanced i n t hei r pr ospect uses, adver t i sement s, and

r epor t s, ar e suf f i ci ent l y monst r ous t o exci t e a smi l e of

i ncr edul i t y on t he count enance of t hei r war mest wel l -

wi sher s, i t i s i n vai n t o deny t hat , as t he means of a

r api d, cheap, and cer t ai n communi cat i on, ever y r ai l way

wi l l , t o a gr eat ext ent , at t r act t he t r af i i c f r om t he

nei ghbour i ng r oads. We may al so f ul l y expect t o see

t he r ai l way syst em ext ended f r om t he mai n t r unks, i nt o

ever y t own of t he l east i mpor t ance wher e t he chances

of r emuner at i on wi l l at al l j ust i f y t he cost of const r uc -

t i on. Many pl aces, not wi t hst andi ng, wi l l be l ef t wi t hout

t he advant age of t hi s r api d and cheap mode of t r ansi t ;

because l ocal ci r cumst ances, ar i si ng somet i mes f r om

t he di f f i cul t nat ur e of t he count r y t o be t r aver sed, and

somet i mes f r om t he obj ect i ons of l anded pr opr i et or s,

wi l l of t en occur t o pr event t he f or mat i on of a r ai l way,

except at a gr eat er out l ay of capi t al t han shoul d ever

be i ncur r ed f or t he pur pose. Under such ci r cumst ances,

i t i s hi ghl y i mpor t ant t hat t he ver y best descr i pt i on of

r oad shoul d be f or med t o communi cat e wi t h t he r ai l way;

ot her wi se, f or t he t owns i n quest i on, t her e i s an end t o

al l chance of compet i t i on wi t h t hose pl aces whi ch

possess t he advant age of communi cat i ng by br anch

r ai l ways wi t h t he mai n t r unk l i ne. New r oads wi l l

B 2

al so i n many cases be f or med, i n or der t o obt ai n a

r eady j unct i on wi t h t he gr eat l i nes of r ai l way ; and of

cour se t he st r ongest r easons exi st f or f or mi ng t hese new

r oads i n t he most per f ect manner .

Sever al of t he t r ust s on t he London and Hol yhead

r ead, ar e at t hi s t i me act i vel y engaged, at t he r ecom-

mendat i on of t he Par l i ament ar y Commi ssi oner s, i n

canni ng i nt o ef f ect ext ensi ve i mpr ovement s i n t he l i ne of

t hat r oad. I n pl ace of r esi gni ng t hemsel ves t o t he f at e of

l osi ng t hei r t r af f i c i n f avour of t he London and Bi r mi ng-

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ham Rai l way, t he commi ssi oner s of t hi s r oad ar e wi sel y

endeavour i ng t o r ai se t he t r avel l i ng t o somet hi ng l i ke

an equal i t y wi t h t hat on t he r ai l way i t sel f ; and i t i s

onl y by adopt i ng such measur es, t hat t he syst em of

common r oads can be expect ed t o st and t he shock of

r ai l way compet i t i on.

But i ndependent of t he i mpr ovement of our gr eat

t ur npi ke- r oads, wi t h t he vi ew of enabl i ng t hem, as f ar

as possi bl e, t o compet e wi t h r ai l ways, a ver y gr eat

necessi t y exi st s, as I have al r eady hi nt ed, f or an ext en-

si ve change i n our syst em of par i sh r oads. I n many

par t s of Engl and, wher e t he most abundant f aci l i t i es

ar e af f or ded by t he pr esence of excel l ent st one, t o f or m

t he ver y best descr i pt i on of r oads, we f i nd t he means

of communi cat i on ver y l i t t l e super i or t o or di nar y car t

t r acks. The weal t h and r esour ces of many ver y f i ne

agr i cul t ur al di st r i ct s ar e t hus, as i t wer e, bound up and

pr event ed f r om bei ng ext ended beyond t he i mmedi at e

nei ghbour hood whi ch pr oduces t hem ; whi l e ever y one

i nt er est ed i n t he success of agr i cul t ur al oper at i ons, i s

wel l abl e t o est i mat e t he i nf l uence whi ch t he condi t i on

of t he r oads exer ci ses upon t he pr ospect s of t he f ar mer .

The evi l s of i l l - f or med and i nsuf l i ci ent r oads, have

been of l at e year s so pr omi nent l y br ought i nt o not i ce,

and ar e now so gener al l y admi t t ed, t hat i t wi l l be

unnecessar y her e t o dwel l on t hem at any l engt h. As

an i nst ance, however , of t he i mmense soci al i mpr ove-

ment whi ch has been ef f ect ed i n a nei ghbour i ng count r y,

by means of a j udi ci ous syst em of i nl and communi ca-

t i on, I cannot f or bear adver t i ng t o t he past and pr esent

st at e of t he Hi ghl ands of Scot l and. For t y year s ago,

i n t r avel l i ng t hr ough t hat count r y, t he eye of t he

obser ver wander ed over vast t r act s of uncul t i vat ed and

appar ent l y bar r en moor l and, whi ch af i br ded a scant y

subsi st ence t o t he sheep whi ch past ur ed upon i t . The

heat her and whi n, or gor ze- f ur ze bushes, wi t h t he

shor t gr ass pecul i ar t o mount ai nous di st r i ct s, composed

t he onl y cr ops of t hose uncul t i vat ed t r act s, whi ch of

cour se wer e t hen ent i r el y wi t hout r oads or ot her means

of i nt er nal communi cat i on. I t f or ms a cur i ous sequence

i n t he chai n of human event s, t hat a boon so f r aught

wi t h nat i onal benef i t , as t he est abl i shment of good

r oads t hr oughout t he Hi ghl ands, ar ose out of a nat i onal

cal ami t y, of no l ess i mpor t ance t han t he unf or t unat e

r ebel l i on of 1745. The Gover nment , who wi t h equal

wi sdom and l i ber al i t y, had r esol ved on r est or i ng t o t he

count r y t he money ar i si ng f r om est at es at t hat t i me

f or f ei t ed t o t he Cr own, of f er ed t o advance one moi et y

of t he sum necessar y t o f or m a per f ect syst em of r oads,

on condi t i on t hat t he l anded pr opr i et or s woul d r ai se

t he ot her moi et y among t hemsel ves. Thi s was accor d-

i ngl y done ; and under Mr . Tel f or d' s management , as

engi neer , t he count r y was i nt er sect ed by r oads i n ever y

di r ect i on. The r esul t has been, t hat t he l ow gr ounds,

or gl ens as t hey ar e cal l ed, now abound i n r i ch past ur es,

whi l e f i el ds of f er t i l e cor n suppl y t he pl ace of t he wi l d

heat her of t he hi l l s, and now wave t o t he bl ast whi ch

f or mer l y swept unr esi st ed over a t r ackl ess moor . The

i nhabi t ant s of t hese di st r i ct s, shut out as t hey wer e

f r om communi cat i on wi t h t he r est of t he wor l d, wer e

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6

wel l known t o exi st i n a st at e of r emar kabl e i gnor ance

and degr adat i on. But now t hei r condi t i on i s wi del y

di f f er ent

t he busy voi ce of human i ndust r y ascends

f r om ever y val l ey

r api d st r i des have been made i n t he

cul t i vat i on of many usef ul ar t s

and pauper i sm, at

l east t hat ki nd r equi r i ng t he ai d of char i t y, i s al most

unknown.

These ar e a f ew of t he si gns of pr osper i t y and

nat i onal weal t h, whi ch at once occur t o t he st r anger

t r avel l i ng t hr ough t hi s count r y ; and i f he shoul d l ook

f ur t her i nt o i t s condi t i on, he wi l l f i nd a popul at i on

happy, devot i onal , cont ent ed wi t h t hei r st at i on, and

al i ke di st i ngui shed f or mor al pr i nci pl e and per sever i ng

i ndust r y.

The expense of t he r oads t hus const r uct ed t hr ough-

out t he Nor t h of Scot l and, has cer t ai nl y been ver y

gr eat ; but i t i s no l ess t r ue, t hat t he advant ages der i ved

and t he benef i t s conf er r ed, woul d have ampl y j ust i f i ed,

and been cheapl y pur chased by, t he out l ay even of

doubl e or t r ebl e t he capi t al act ual l y expended ; f or , i n

addi t i on t o t he i mmense i mpr ovement i nt r oduced i nt o

t he agr i cul t ur e of t he count r y, t he whol e l i ne of coast

has become t he seat of ext ensi ve and f l our i shi ng

f i sher i es, whi ch af i br d empl oyment t o a vast popul at i on.

Docks and har bour s have been const r uct ed i n ever y

f avour abl e si t uat i on; whi l e communi cat i ons bet ween

pl aces i n t he i nt er i or and wi t h t he coast , ar e made wi t h

r egul ar i t y and di spat ch. Ever y f aci l i t y t hus gi ven,

has wel l succeeded i n conf er r i ng t he bl essi ngs of act i ve

commer ce upon a count r y, wher e i ndust r y i s, per haps,

mor e necessar y t o t he enj oyment of comf or t , t han i n

al most any ot her on t he f ace of t he gl obe.

Now, wi t hout meani ng t o i nf er t hat any par t of

Engl and i s so def ect i ve i n t he means of communi cat i on,

as t he Hi ghl ands of Scot l and, bef or e t he i mpr ovement s

I have descr i bed, and whi ch wer e ef f ect ed by t he Hi gh-

l and Roads' and Br i dges' Commi ssi on, I woul d st i l l

suggest , t hat some compar i son mi ght be made bet ween

t he t wo cases ; and t he success whi ch has at t ended t he

i mpr ovement s made i n Scot l and, wi l l at l east f ur ni sh

an ar gument f or t he i mpr ovement of our or di nar y r oads

i n Engl and. I t i s no doubt an i mmense advant age t o a

count r y, t o be t r aver sed by good t ur npi ke- r oads ; but

t he val ue of t hese i s much l essened, when t hey can onl y

be r eached by means of t he execr abl e r oads whi ch at

pr esent l ead out of t hem, t o t he var i ous vi l l ages and

f ar m- houses, not si t uat ed on t he exact l i ne of r oad.

The f ar mer , i n conveyi ng hi s cor n and ot her pr oduce

t o mar ket , and i n sendi ng manur e t o hi s f i el ds, may

comf or t hi msel f wi t h t he r ef l ect i on, t hat whi l st hi s

hor ses ar e on t he t ur npi ke- r oad t hey wi l l not be

i nj ur ed by t he l oads t hey have t o dr aw ; but what i ^

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t hei r si t uat i on unt i l t hey r each t he t ur npi ke- r oad, and

af t er t hey l eave i t ? Of cour se, wher e t he t ur npi ke l i es

i n such a di r ect i on as not t o be avai l abl e, t he case wi l l

be wor se t han wher e i t can be par t i al l y used. But even

i n t he most f avour abl e case, i t i s evi dent , t hat t he

f ar mer must be cont ent wi t h a much l ess l oad t han hi s

hor ses coul d dr aw on t he t ur npi ke- r oad, unl ess he

at t empt t o car r y mor e t han a f ai r l oad on t he bad r oads

t o be passed over , l eadi ng i nt o or out of t he t ur npi ke-

r oad. On t he ot her hand, i f he put s on a f ai r l oad f or

t he t ur npi ke- r oad, hi s hor ses wi l l be much over l oaded

when t hey come on t he i nf er i or ki nd of r oad ; because

a hor se, whi ch on t he f or mer i s abl e t o dr aw a t on

wei ght wi t h ease, woul d pr obabl y on t he l at t er be

unabl e t o move wi t h mor e t han f i ve or si x hundr ed

wei ght . The i nj ur i ous ef f ect s of t hi s ar e t oo obvi ous t o

r equi r e comment ; and t hey est abl i sh a st r ong r eason

why al l r oads shoul d be r educed, as near l y as possi bl e.

8

t o an equal i t y i n poi nt of dr aught . I t coul d har dl y be

expect ed, nor i s i t necessar y, t hat t he same br eadt h

and f i ni sh shoul d be gi ven t o al l r oads, whi ch ar e ver y

pr oper l y adopt ed on t he mai n l i nes of t ur npi ke; but I

am deci dedl y of opi ni on, t hat al l r oads ought t o be

equal l y har d and sol i d ; and T woul d make ever y par i sh

and ever y occupat i on or f ar m- r oad t hr oughout t hi s

count r y, as excel l ent i n t hi s essent i al poi nt as t he

gr eat Hol yhead r oad i t sel f . For r oads wher e no gr eat

t r af f i c exi st s, t he br eadt h i s of l i t t l e consequence; but

on t hi s ki nd of r oad t he vehi cl es whi ch do pass over

i t ar e usual l y f ar m waggons, cont ai ni ng as heavy

wei ght s as any on t he t ur npi ke- r oads. The unf r e-

quent ed r out es shoul d t her ef or e be as capabl e of car -

r yi ng heavy t r af f i c as t he gr eat r oads t hemsel ves ; and

t hi s t hey can onl y be when f or med wi t h a f i r m un-

yi el di ng f oundat i on, accor di ng t o one or ot her of t he

met hods whi ch wi l l her eaf t er be descr i bed.

I obser ve t hat , dur i ng t he pr esent sessi on, a Bi l l has

been br ought i nt o Par l i ament by Mr . Shaw Lef evr e and

Mr . Mi l dmay, " t o aut hor i ze t he appl i cat i on of a por -

t i on of t he hi ghway r at es t o t ur npi ke- r oads i n cer t ai n

cases. " By t he Act of t he 5i h and 6t h Wi l l . I V. c. 50,

t he per f or mance of st at ut e dut y f or t he pur pose of up-

hol di ng t he r oads was abol i shed; and t he pr esent Bi l l i s

i nt ended, amongst ot her t hi ngs, t o conf i r m t he pr ovi -

si ons of t hat Act ; and wi t h t hi s vi ew i t i s pr oposed t o

be enact ed, " t hat no per son i s l i abl e t o per f or m any

st at ut e l abour upon any t ur npi ke- r oad i n Engl and, or

t o pay any composi t i on i n money i n l i eu t her eof . "

The ol d met hod of suppor t i ng t he t ur npi ke- r oads bei ng

t hus abol i shed, t he Bi l l pr oceeds t o enact , t hat j ust i ces

of peace may i nqui r e at speci al sessi ons f or hi ghways

i nt o t he r evenues and condi t i on of t he r epai r s of t ur n-

pi ke- r oads, and i f necessar y may appor t i on a par t of

9

Page 7 of 103

t he hi ghway r at e t o t he t r ust ees of t he t ur npi ke- r oad ;

and t he money so r ecei ved i s t o be whol l y l ai d out i n

t he act ual r epai r of such par t of such t ur npi ke- r oad as

l i es wi t hi n t he par i sh f r om whi ch i t was r ecei ved.

I t seems l i kel y, t hat t he condi t i on of t he t ur npi ke-

r oads wi l l be much benef i t ed by t he pr ovi si ons of t hi s

Bi l l , shoul d i t r ecei ve t he sanct i on of Par l i ament . Many

of t he t r ust s on t hese r oads ar e now so ser i ousl y i m-

pover i shed, t hat t he sums t hey may t hus cl ai m f r om t he

hi ghway r at es wi l l be of i j r eat ser vi ce, and t he f ar mer s

wi l l al so be r el i eved f r om what i n some cases may be

consi der ed an oppr essi ve bur den ; but whet her t he

l evyi ng- of hi ghway r at es t o t he ext ent whi ch wi l l be

r ender ed necessar y by t hi s Act , wi l l not pr ess wi t h

undue sever i t y i n ot her quar t er s, i s a quest i on I am

unabl e t o answer . I t w oul d al so be mat t er of gr eat

compl ai nt , i f t he or di nar y hi ghways, not bei ng t ur n-

pi kes, shoul d become wor se of f t han at pr esent . I t

woul d r equi r e ver y l i t t l e ar gument t o pr ove t hat t hese

r oads st and ver y much i n need of i mpr ovement ; and

shoul d t he sur veyor s be r ender ed l ess abl e t o suppor t

t hem t han at pr esent , Ave may soon expect t o see t hem

al most i mpassabl e.

I have al r eady al l uded t o t he necessi t y f or some ex -

t ensi ve i mpr ovement i n our syst em of common r oads ;

and as t hi s i mpr ovement woul d be pr i nci pal l y ef f ect ed

by means of manual l abour , i t mi ght be made at a ver y

smal l out l ay of capi t al , and woul d af f or d empl oyment

t o t he vast number s of pauper s who now cr owd t he

wor khouses of t hi s count r y. I t i s t r ue, t hat at t empt s

have al r eady been made i n some pl aces t o i mpr ove t he

r oads by empl oyi ng t he pauper s upon t hem ; but I con-

t end t hat t hei r l abour has not hi t her t o been pr oper l y

appl i ed, and i n f act unt i l t hey ar e made t o wor k upon

a r egul ar syst em, and under pr oper management , i t wi l l

10

be unr easonabl e t o expect any r emar kabl e r esul t f r om

t hei r l abour s. An excel l ent oppor t uni t y i s now af f or ded

t o t he guar di ans of t he poor t hr oughout t he count r y, t o

assi gn t he sur veyor of hi ghways a cer t ai n number of

t he most abl e bodi ed pauper s, t o be empl oyed i n t he

i mpr ovement of t he common r oads; and i f t he l abour er s

so empl oyed wer e pai d a t r i f l i ng sum i n addi t i on t o t he

wor khouse al l owance, t hey woul d soon become usef ul

i n per f or mi ng t he t ask assi gned t o t hem. I n my opi ni on,

i t i s al most i mpossi bl e t o concei ve t he ext ent of benef i t

whi ch wi l l ar i se f r om t he empl oyment of l abour i n t he

manner I have suggest ed : but i t i s necessar y t o obser ve,

t hat t he sur veyor s shoul d be made t o act on a f i xed

syst em, because t he count r y has al r eady suf f i ci ent l y

suf f er ed f r om t he i gnor ance and i ncapaci t y by whi ch

t oo many of t hi s cl ass ar e di st i ngui shed. Wr i t t en i n-

st r uct i ons i n t he f or m of speci f i cat i ons shoul d be dr awn

out by compet ent engi neer s, pr act i cal l y exper i enced i n

t he const r uct i on and management of r oads ; and t o t hese

i nst r uct i ons, whi ch shoul d be adapt ed t o par t i cul ar di s -

t r i ct s of count r y, t he sur veyor s shoul d be bound st r i ct l y

Page 8 of 103

t o adher e. A gener al knowl edge of t he pr i nci pl es of

r oadmaki ng woul d t hus be di f l used, and at no di st ant

per i od, we mi ght expect t o r eap t he advant ages of t hi s

syst em. A scal e of pr i ces shoul d be est abl i shed f or

t he payment of t he l abour er s by measur ement of t he

wor k per f or med, and not , as t hey ar e usual l y pai d, by

day wor k. Thi s l at t er cust om i s ext r emel y bad, be-

cause i t s cer t ai n consequence i s t o r educe al l t he

wor kmen t o one uni f or m st at e of i ndol ence and i nef f i -

ci ency. To t he mi nds of men so empl oyed, no advan-

t age pr esent s i t sel f f r om t he exer t i on of any t hi ng l i ke

super i or i ndust r y. Si nce al l t he l abour er s ar e pai d

al i ke, i t i s evi dent t hat t he best wor kmen, or t hose

who under ot her ci r cumst ances woul d become good

11

wor kmen, have no possi bl e i nducement t o exer t t hem-

sel ves mor e t han t he i dl est and weakest of t he whol e

gang. Hence t he power and ener gi es of t hese men ar e

par al yzed t o an ext r aor di nar y ext ent ; and i t i s f r i ght f ul

t o r ef l ect on t he ser i ous and accumul at ed evi l s ar i si ng

f r om t he ver y i nj udi ci ous way i n whi ch t hey ar e em-

pl oyed by t he over seer s. To t he oper at i on of t hi s syst em

al one, t he over seer s ar e i ndebt ed f or r epeat ed f ai l ur es

i n t hei r at t empt s t o empl oy t he poor wi t h advant age.

I f , however , t hese ver y same men wer e empl oyed at a

f ai r r emuner at i ng pr i ce i n pr opor t i on t o t he wor k t hey

per f or m, t her e exi st s no r eason on ear t h why t hey

shoul d f ai l t o obt ai n an honest subsi st ence f or t hei r

f ami l i es ; and at t he same t i me, t he par i shes and t he

count r y wi l l der i ve a r eal and sol i d advant age f r om t he

out l ay of capi t al i n t he shape of poor r at es. The ad-

vant age t o be der i ved f r om t he change of syst em I

have r ecommended, i s si mpl y t hi s, t hat t he money

expended i n r el i evi ng abl e- bodi ed pauper s, i nst ead of

pr oduci ng ver y l i t t l e or no pr of i t abl e r esul t , may be

appl i ed i n t he most usef ul manner , as par t payment

f or t he wor k done by pauper s, i n t he i mpr ovement of

t he r oads.

I n t he succeedi ng chapt er s I shal l endeavour t o

poi nt out a syst emat i c mode of i mpr ovi ng t he r oads,

i n whi ch t he pr i nci pal i ngr edi ent wi l l consi st of act ual

l abour . I f I coul d show no ot her means of i nt r oduci ng

ef f ect ual i mpr ovement s t han t he appl i cat i on of expen-

si ve mat er i al s, and t he consequent out l ay of consi der -

abl e f unds, I shoul d consi der i t usel ess t o devot e

at t ent i on t o t he subj ect ; but wi t h t he di f f er ent opi ni ons

I have vent ur ed t o expr ess, and wi t h di f f er ent obj ect s

i n vi ew t han t o r ecommend ext r avagant expendi t ur e, I

pr oceed t o t he pr act i cal det ai l s of t he subj ect .

\ \ bi e* ^ ^ ^ ' "

100} ^

Page 9 of 103

/ , . : i i

I V - 1- .

C/ c/ /

12

} l ' , :

CHAPTER I I .

On t he Met hod of i mpr ovi ng an exi st i ng Road.

The

Fi gur e or Pr of i l e whi ch shoi dd be gi ven t o t he Bed

and Sur f ace.

For mi ng t he Foot - pcdl i and Fences.

As a f i r st st ep t o i mpr ove t he condi t i on of an ol d

r oad, t he di r ect i on and gener al l evel s of whi ch cannot

be al t er ed, I shoul d pr oceed t o cat down hi gh f ences,

i f t hese exi st , on each si de of t he r oad, and r egul ar l y

t o t r i m t he hedges, so t hat t he hei ght of t he bank and

f ence shoul d not exceed f our or f i ve f eet above t he

l evel of t he r oad. The sof t mud shoul d t hen be scr aped

f r om t he sur f ace, and t he bed of t he r oad f or med wi t h

a r egul ar convexi t y of one i nch i n f i ve f eet , whi ch wi l l

gi ve i n a r oad of t hi r t y f eet wi de, a r i se of ni ne i nches

i n t he cent r e. I n advanci ng t he opi ni on, t hat t he bed

of t he r oad shoul d be f or med wi t h a cur ved sur f ace,

I am at var i ance wi t h t he doct r i ne of many r oad-

maker s, who cont end t hat t he r oad mat er i al shoul d be

l ai d on a f l at sur f ace. The pr i nci pal r eason whi ch has

i nduced me t o adopt t he pr act i ce of cur vi ng t he bed i s,

t hat t he dr ai nage i s her eby r ender ed mor e easy and

ef f ect ual , and t he cur ved f i gur e of t he r oad on t he

upper sur f ace i s pr eser ved, by l ayi ng on t he r oad

cover i ng of equal dept h ent i r el y acr oss t he r oad. Her e

agai n a ver y common opi ni on i s, t hat t he dept h of

mat er i al i n t he cent r e of t he r oad sl i oul d be gr eat er

t han at t he si des ; but f or my par t , I have never been

abl e t o di scover why t he si des of t he r oad sl i oul d be at

al l i nf er i or t o t he mi ddl e i n har dness and sol i di t y. On

13

t he cont r ar y, i t woul d be a gr eat i mpr ovement i n

gener al t r avel l i ng, i f car r i ages coul d be made t o adher e

mor e st r i ct l y t o t he r ul e of keepi ng t he pr oper si de of

t he r oad; and t he r easonabl e i nducement t o t hi s pr ac -

t i ce i s obvi ousl y t o make t he si des equal l y har d and

sol i d wi t h t he cent r e. I n many r oads, even wher e con- " Sr

Page 10 of 103

si der abl e t r af f i c exi st s, t he onl y good par t of t he r oad /

consi st s of about ei ght or t en f eet i n t he cent r e, t he ' ;

si des bei ng f or med wi t h smal l gr avel qui t e unf i t t o

car r y heavy t r af f i c ; and t he consequence i s, t hat t he

whol e cr owd of vehi cl es i s f or ced i nt o t he cent r e t r ack

of t he r oad, t hus at l east doubl i ng or t r ebl i ng t he wear

- '

and t ear whi ch woul d t ake pl ace i f t he si des wer e as

t hey ought t o be, equal l y good wi t h t he cent r e. Anot her

mi schi evous consequence i s, t hat when i t becomes

necessar y t o r epai r t he cent r e of t he r oad, t he car r i ages

ar e dr i ven of f t he onl y good par t on t o t he si des, whi ch ^

consi st of weak mat er i al , and ar e of t en even danger ous

f or t he passage of heavi l y l aden st age coaches. On

t he ot her hand, i f equal l abour and mat er i al s be ex - r

pended on t he whol e br eadt h of t he r oad, i t i s evi dent i

t hat t he wear and t ear wi l l be f ar mor e uni f or m ; and

when any one par t r equi r es r epai r , t he t r af f i c may wi t h

saf et y be t ur ned on t o anot her par t . Hence I shoul d ,

al ways l ay on t he same dept h of mat er i al al l over t he 1 _^

r oad ; and t hi s al one wi l l of cour se r ender i t necessar y

t o cur ve t he bed of t he r oad. Wi t h r espect t o t he

ki nd of cur ve t o be f or med, I t hi nk t he segment of a

l ar ge ci r cl e, i n whi ch t he chor d of t hi r t y f eet shal l have

a r i se or ver sed si ne of about ni ne i nches, wi l l f or m

j ust as good a r oad as t he segment of an el l i psi s adopt ed

by some engi neer s. The ci r cl e, wi t h t he ci r cumf er ence

of whi ch I woul d r ecommend t hat bot h t he bed of t he

r oad and i t s upper sur f ace shoul d coi nci de, woul d be

f or med wi t h a r adi us of 150 f eet ; and as a gui de f or

\ '

14

t he wor kman i n maki ng t he pr oper sect i on, i t woul d be

ver y usef ul t o pl ace i n hi s hands a j j i ece of boar d,

havi ng one of i t s edges cur ved t o t he pr oper f i gur e, and

t hi s edge bei ng appl i ed t o t he r oad sur f ace, wi l l at

once det er mi ne t he coi TCct degr ee of cur vat ur e.

I n many r oads, wher e t he t hor oughf ar e i s not ver y

ext ensi ve, a f oot pat h and ver ge may be t hought an un-

necessar y addi t i on t o t he expenses ; and cer t ai nl y, i n

i mpr ovi ng t he or di nar y f ar m and occupat i on r oads, i t

i s nat ur al t o suppose t hat l abour and capi t al woul d be

expended t o t he gr eat est advant age i n f or mi ng a har d

and sol i d t r ack f or waggons and car t s. I n t he case of

t hese r oads, t he br eadt h of r oadway i s of cour se not

ver y i mpor t ant . I t i s har dl y possi bl e t o f or m any

adequat e i dea of t he benef i ci al ef f ect s whi ch woul d

ar i se f r om t he const r uct i on of even t en f eet i n wi dt h,

of har d sol i d r oad, i n pl ace of a br oken uneven sur -

f ace, deepl y f ur r owed by t he f r i ght f ul r ut s i nvar i abl } ^

Page 11 of 103

f ound i n t hese r oads.

I n f or mi ng t he bed of a r oad, bef or e const r uct i ng

t he f oundat i on, whet her t hi s i s t o consi st of pi t ched

st ones or of concr et e, as her eaf t er descr i bed, i t shoul d

be bor ne i n mi nd, t hat i f t he subst r at um be t ol er abl y

f i r m, t he nat ur al sur f ace of t he gr ound shoul d be di s -

t ur bed as l i t t l e as possi bl e. The pr act i ce of f or mi ng

t he bed of a r oad bel ow t he nat ur al sur f ace i s deci dedl y

bad, wher ever i t can be avoi ded. I t adds consi der -

abl y t o t he di f f i cul t y of dr ai nage, and t he onl y good

whi ch i t can ef i ' ect

namel y, t o f or m def i ned boundar i es

or edges f or t he car r i age r oad- way on each si de,

can

be equal l y wel l done by a l i t t l e ear t h or moul d, and a

t ur f pl aced on edge al ongsi de t he f oot pat h and ver ge.

I f t he r oad i s t o be met al l ed over a t r act cover ed wi t h

gr een swar d, t hi s shoul d be al l owed t o r emai n, and t he

pi t chi ng or concr et e l ai d i mmedi at el y upon i t , wi t h t he

15

except i on mer el y, t hat t he gr ound shoul d be r ounded

of f t o t he necessar y convexi t y, t he mi ddl e par t or cent r e

of t he r oad t r ack r emai ni ng undi st ur bed. Anot her me-

t hod of f or mi ng t he convexi t y i n t he bed of a r oad,

whi ch may of t en be f ol l owed wi t h advant age, i s t o l ay

on t he nat ur al sur f ace a suf f i ci ent quant i t y of t he ear t h

t aken f r om t he di t ches, t o f or m t he r equi r ed f i gur e, and

i f t hi s ear t h be wel l pounded, t he concr et e or pi t chi ng

st ones may saf el y be pl aced upon i t . Thi s, however ,

must never be at t empt ed unl ess t he mat er i al be har d

and por ous, such as sand, gr avel , or r ubbl y r ock, f or

any descr i pt i on of cl ay or mud woul d f or m a ver y

unsound bot t om.

The f ol l owi ng chapt er s wi l l descr i be so f ul l y t he

met hod of pi t chi ng t he r oad wi t h st ones pl aced on

edge, and t he met hod of f or mi ng a concr et e f oundat i on

f or t he r oad mat er i al , t hat i t wi l l be unnecessar y i n t hi s

pl ace t o ent er upon t hat par t of t he subj ect . I t may

not however be f or ei gn t o t he busi ness of t hi s chapt er ,

t o make some r emar ks on t he upper cover i ng of t he

r oad above t he pi t chi ng or concr et e. I n l ayi ng on t hi s

upper cover i ng, many sur veyor s commi t a gr eat er r or

i n not maki ng a di st i nct di f f er ence bet ween angul ar or

br oken st ones, and t hose r ounded smoot h pebbl es of

whi ch gr avel i s usual l y composed. The f or mer cannot

be t oo wel l cl eaned bef or e bei ng l ai d on t he r oad,

because even when ent i r el y di vest ed of al l ear t hy

mat t er , t hey soon become wedged and bound cl osel y

t oget her , when t he pr essur e of car r i ages comes upon

t hem. But t he case i s di f f er ent wi t h t he smoot h r ound

sur f aces of gr avel ; f or i f t hi s mat er i al be ent i r el y

cl eaned by means of washi ng and r epeat ed si f t i ngs,

t he pebbl es wi l l never bi nd, unt i l i n a gr eat measur e

t hey become gr ound and wor n down by t he const ant

pr essur e and r ubbi ng agai nst each ot her . Bef or e t hi s

I G

Page 12 of 103

t akes pl ace, t he sur f ace of t he r oad must be consi der abl y

weakened, and wi l l i n f act be i ncapabl e of suppor t i ng

t he pr essur e of heavy wheel s, whi ch consequent l y si nk

i nt o i t , and meet wi t h consi der abl e r esi st ance t o t hei r

pr ogr ess. Under t hese ci r cumst ances, i t seems t hat

t he pr act i ce of t oo scr upul ousl y cl eani ng t he r ounded

pebbl es of gr avel , must be deci dedl y condemned; and

t he quest i on t hen ar i ses, t o what ext ent shoul d t he

cl eani ng pr ocess be di spensed wi t h ; or , i n ot her wor ds,

what pr opor t i on of t he bi ndi ng mat er i al f ound i n t he

r ough gr avel , as t aken out of t he pi t , shoul d be al l owed

t o r emai n i n t he mass i nt ended t o be pl aced on t he

r oad ? I n answer t o t hi s i nqui r y I shoul d i nf er , f r om

t he nat ur e of t he bi ndi ng r equi r ed, i n or der t o f or m a

pr oper sur f ace f or t he r oad, t hat t he l east quant i t y of

ear t hy mat er i al whi ch ought t o r emai n amongst t he

smoot h pebbl es, i s pr eci sel y t hat quant i t y whi ch woul d

f i l l up t he i nt er st i ces of a por t i on of t he cl ean gr avel ,

wi t hout addi ng t o i t s cubi cal cont ent s. The pr opor -

t i on necessar y f or t hi s pur pose, may be det er mi ned by

t he f ol l owi ng exper i ment : Take any gi ven mass, say

one cube yar d, of per f ect l y cl ean washed gr avel ,

ent i r el y di vest ed of ever y par t i cl e of adher i ng mat t er ,

and pl ace i t i n a box or t r ough, cont ai ni ng t he same

cubi cal cont ent s ; t hen pour i n wat er t i l l i t r i ses t o t he

sur f ace, when i t i s evi dent t hat t he cubi cal capaci t y of

t he wat er so empl oyed, wi l l r epr esent exact l y t hat

quant i t y of mat t er whi ch wi l l f i l l up al l t he vacui t i es

bet ween t he pebbl es, and r et ai n t hem f i r ml y i n t hei r

pl aces, under t he pr essur e of any wei ght passi ng over

t hem. Hence t he r eason f or supposi ng t hat t hi s shoul d

be t he mi ni mum quant i t y of bi ndi ng mat er i al , t o be l ef t

i n t he gr avel bef or e pl aci ng i t on t he r oad. I n act ual

pr act i ce i t may be f ound unnecessar y t o r esor t t o t hi s

exper i ment ; and even wher e i t can be made, i t wi l l

17

har dl y be possi bl e t o deci de on t he exact ki nd of si eves

t hr ough whi ch t he gr avel shoul d be passed, and t he

ot her pr ocesses t o whi ch i t shoul d be subj ect ed, i n

or der t hat nei t her mor e nor l ess t han t he pr eci se pr o-

por t i on of ear t hy mat t er shoul d r emai n i n t he pr epar ed

gr avel . The exper i enced sur veyor , however , woul d be

abl e af t er a l i t t l e exami nat i on t o j udge of t he ext ent t o

whi ch t he gr avel shoul d be cl eaned. A l ong cour se of

exper i ence, accompani ed by at t ent i ve obser vat i ons on

t hese det ai l s i n t he pr act i ce of r oadmaki ng, has con-

vi nced me, t hat i t i s much bet t er and saf er , as a gener al

r ul e, t o l eave t oo much of t he bi ndi ng mat er i al i n t he

gr avel , t han t o di vest i t t oo compl et el y of t hi s sub-

st ance. When t he gr avel i s pl aced on a r oad wi t hout

bei ng suf f i ci ent l y cl eaned, t he const ant wear and t ear ,

ai ded by t he occur r ence of wet weat her , causes t he

har der mat er i al or act ual gr avel t o be pr essed cl ose t o-

get her ; and t he sur pl us of sof t bi ndi ng mat er i al r emai n-

i ng af t er t he i nt er st i ces bet ween t he pebbl es ar e f i l l ed

up, bei ng t hen f or ced t o t he t op, and usual l y mi xed wi t h

wat er , becomes mud, and accor di ng t o t he usual pr act i ce

shoul d be scr aped t o t he si des of t he r oad. When t hi s

has been done t he sur f ace i s usual l y f i r m and sol i d ;

because t he har d gr avel bel ow t he mud has become

Page 13 of 103

per f ect l y bound, wi t hout at t he same t i me bei ng br oken

or gr ound t o pi eces. Suppose next a r oad cover ed

wi t h gr avel t oo much cl eaned, wher e i t i s evi dent t hat

t he dest r uct i on of t he gr avel wi l l cont i nue unt i l i t

becomes br oken i nt o angul ar pi eces, and a suf f i ci ent

quant i t y of pul ver i zed mat er i al has been f or med

t o hol d t he st ones i n t hei r pl aces and t hus t o ef f ect

t he bi ndi ng of t he mass. I need har dl y say, t hat t he

det er i or at i on t hus occasi oned t o t he r oad i s an evi l

of much mor e i mpor t ance, and one much mor e t o be

avoi ded, t han t hat occasi oned by empl oyi ng st ones not

c

18

suf f i ci ent l y cl eaned. Regar dl ess of al l t hi s, however ,

i t i s t he pr act i ce of many r oad sur veyor s, t o i nsi st t hat

al l gr avel of what ever qual i t y shal l be r ender ed per -

f ect l y cl ean by r epeat ed si f t i ngs, and even by washi ng,

unt i l at l ast i t becomes ent i r el y di vest ed of al l t hat

may pr oper l y be consi der ed t he bi ndi ng par t of t he

mat er i al .

The qual i t i es of gr avel ar e so exceedi ngl y var i ous,

t hat i t i s i mpossi bl e t o l ay down any gener al r ul e as t o

t he pr epar at i on i t shoul d under go bef or e bei ng used on

t he r oad. The pr i nci pal var i et i es consi st of quar t z or

si l ex, and ar e usual l y t he det r i t us of t he ol der r ocks.

Consi der abl e beds of gr avel ar e how^ ever f or med of t he

f l i nt s whi ch have been washed f r om t he upper chal k

st r at a ; and i n t he west of Engl and, t he det r i t us of t he

ool i t i c r ocks f or ms ext ensi ve deposi t s of gr avel . Those

var i et i es usual l y r equi r e t he l east cl eani ng whi ch ar e

mi xed wi t h shar p angul ar par t i cl es of sand, somet i mes

i mpr egnat ed wi t h i r on ; and i n f act , a gr eat deal of

t hi s ki nd of gr avel may be used on t he r oads af t er bei ng

once si f t ed, as i t sel dom r equi r es any washi ng. Some

of t he f l i nt gr avel r equi r es l i t t l e pr epar at i on, except t hat

of br eaki ng t he l ar ger l umps t o a sui t abl e si ze, whi ch

shoul d not much exceed t hat of a l ar ge hen' s e^ ^ : but

t hi s i s not al ways t he case ; f or I have met wi t h t hi s

ki nd of gr avel i n a ver y di r t y st at e, much mi xed wi t h

chal k and cl ay, and r equi r i ng a good deal of pr epar a-

t i on bef or e i t coul d be used. Thi s ki nd of gr avel i s

of t en f ound deposi t ed i n ext ensi ve t r act s of l ow f l at

l and ; but t he cl eanest ki nd of f l i nt gr avel i s gener al l y

f ound i n dr y moor l and, el evat ed above t he nat ur al

dr ai nage of t he count r y. The f ol l owi ng ext r act , f r om

one of t he speci f i cat i ons f or an i mpr ovement on t he

Hol yhead r oad, cont ai ns Mr . Tel f or d' s di r ect i ons on t he

pr epar at i on of gr avel f or I hc r oad cover i ng :

19

* ' The ei ght een f eet mi ddl e of t hi s r oad i s t o be

cover ed wi t h t he best gr avel or pebbl es t he count r y

af t br ds; i t must be washed and br oken, so t hat no st one

shal l r emai n or be put on t he r oad t hat wi l l exceed t wo

i nches and a hal f , or be l ess t han one i nch i n di amet er .

Page 14 of 103

Al l t he gr avel i nt ended f or t he ei ght een f eet mi ddl e of

t he r oad t o be r i ddl ed t hr ough t hr ee- quar t er - i nch si eves;

al l t hat passes t hr ough t o be kept f or t he si des. The

si des of t he r oad t o be of gr avel , but i t need not be so

l ar ge as t hat used f or t he cent r e. I t must be washed

and r i ddl ed on si eves of one quar t er i nch meshes ; t he

scr eeni ngs t o be kept f or t he f oot pat h. The whol e

sur f ace t o be cover ed wi t h one i nch and a hal f of good

bi ndi ng gr avel . "

The f ol l owi ng i s f r om a speci f i cat i on by t he same

emi nent engi neer , i n a case wher e t he r oad i mpr ove-

ment was made t hr ough t he st r eet of a t own ( Fenny -

St r at f or d) :

* ' The whol e wi dt h of pavement i s t o be cover ed wi t h

br oken l i mest one t wo i nches t hi ck ; t he mi ddl e ei ght een

f eet of t hi s i s t hen t o be cover ed wi t h f our i nches i n t hi ck -

ness of t heHar t shi l l st one, br oken so t hat no pi ece shal l

exceed t wo i nches and a hal f i n t he l ongest di agonal

l i ne, or be l ess t han wi l l pass t hr ough a si eve of t hr ee-

quar t er i nch meshes, on whi ch i t must be r i ddl ed t o f r ee

i t f r om di r t bef or e i t i s appl i ed t o t he r oad. The si des

ar e t o be made up of good gr avel , washed, sor t ed, and

br oken i f necessar y. No st one i s t o be l ef t on t he r oad

gr eat er t han wi l l pass t hr ough a r i ng of t wo i nches

di amet er , and al l r ound ones ar e t o be br oken. The

l ar gest assor t ment of gr avel i s t o be put next t he

Har t shi l l st one, and t he smal l er sor t next t he si des of

t he r oad. No gr avel i s t o be put on any par t of t he

r oad t hat wi l l pass t hr ough meshes of hal f i nch squar e.

These gr avel si des ar e t o be f our i nches t hi ck at t he

C 2

20

j unct i on wi t h t he I l ar t shi l l st one, and t wo i nches at

t he si des. "

Foot pat h.

Si mpl e as t he t ask appear s t o be, i t

i s cer t ai n t hat many ver y mi ser abl e f ai l ur es have t aken

pl ace i n t he at t empt t o f or m a good f oot pat h. Thi s

wi l l gener al l y happen when t he mat er i al empl oyed f or

t he pur pose i s of a cl ayey nat ur e, and capabl e of hol d-

i ng wat er . The ear t h t aken out of t he di t ches, f or

exampl e, i s usual l y ver y unf i t t o be pl aced i n t he f oot -

pat hs, and shoul d t her ef or e be r eser ved t o f or m t he

l ower par t of t he mounds or banks f or t he qui ckset s.

The best met hod of const r uct i ng a good f oot pat h, i s t o

r ai se i t by l ayer s of about t hr ee i nches i n t hi ckness,

composed of t he scr api ngs of t he r oad usual l y cal l ed

r oad- dr i f t . Si l t y sand, or smal l gr avel of a bi ndi ng

nat ur e, or t he si f t i ngs of coar ser gr avel , wi l l al so f or m

excel l ent f oot pat hs. Each l ayer shoul d be wel l

pounded wi t h a wooden r ammer or pounder , about f i ve

i nches i n di amet er , unt i l made f i r m and sol i d, when

anot her l ayer may be l ai d on and t he pr ocess of pound-

i ng r epeat ed. About f our l ayer s wi l l br i ng t he f oot pat h

t o i t s pr oper l evel ; and t he sur f ace, whi ch shoul d have

t he sl i ght convexi t y of one i nch i n t hr ee f eet , shoul d

t hen be smoot hl y r aked over , and i f possi bl e shoul d

Page 15 of 103

be al l owed t o consol i dat e and har den bef or e cat t l e,

wheel bar r ows, &c. ar e al l owed t o t r avel upon i t .

Wher e i t may be i nconveni ent t o obt ai n a suf f i ci ent

quant i t y of r oad- dr i f t , or such ot her mat er i al as I have

descr i bed f or t he f oot pat hs, i t wi l l be a ver y good pr ac -

t i ce t o f or m t he l ower par t wi t h r ubbl e st ones, wi t h

coar se gr avel , or any ot her por ous mat er i al , on whi ch

may be l ai d a si ngl e t hr ee- i nch l ayer of r oad- dr i f t t o

f or m t he t op of t he pat h. Bef or e concl udi ng t hese r e-

mar ks on t he const r uct i on of f oot pat hs, I cannot f or bear

adver t i ng t o a syst em pur sued by many r oad sur veyor s,

21

of pl aci ng coar se gr avel and l ar ge st ones i n t he upper

par t of t he pat h. Ever y one at al l accust omed t o wal k

on a f oot pat h so f or med, must be awar e of t he ver y un-

pl easant consequences t o t he f eet ; and we may r eadi l y

concei ve t he mi ser y occasi oned t o pedest r i ans, who ar e

compel l ed t o make l ong mar ches on t hi s ki nd of pat h.

The obvi ous r ul e t o be f ol l owed i s, t hat t he upper par t

of t he pat h shoul d al ways be composed of t he f i ne

gr avel or r oad- dr i f t al r eady spoken of , so t hat t he sur -

f ace of t he pat h may be smoot h and uni f or m as wel l as

har d and sol i d,

t he f or mer of t hese qual i t i es bei ng not

a bi t l ess necessar y i n a good f oot pat h t han t he l at t er .

Fenci ng.

I n al l di st r i ct s of count r y wher e t he

f i el ds ar e i ncl osed, i t i s usual and necessar y t o const r uct

a f ence on each si de of t he r oad t o def i ne i t s boundar y

and pr event t r espass. Wal l s bui l t of dr y r ubbl e st one

ar e a ver y common ki nd of f ence, i n pl aces wher e sui t -

abl e st one abounds; and wi t h r espect t o t hese ver y l i t t l e

need be sai d

t hei r const r uct i on i s so si mpl e and gene-

r al l y so wel l under st ood by t he count r y wal l er s, as t hey

ar e cal l ed, t hat we may pass at once t o t he common

qui ckset hedge mor e gener al l y er ect ed as a f ence.

Di f f er ent opi ni ons ar e ent er t ai ned as t o t he number

of pl ant s whi ch shoul d be pl aced i n a gi ven l engt h, i n

or der t o f or m t he best ki nd of hedge. I t seems how-

ever t o be gener al l y admi t t ed, t hat t he qui cks shoul d

be pl ant ed ei t her when t he sap i s descendi ng i nt o t he

gr ounder ascendi ng i nt o t he pl ant ; t hat i s, ei t her i n t he

aut umn or spr i ng of t he year . Upon t he whol e, I t hi nk

mysel f t he aut umn i s t he most sui t abl e t i me, and i f t he

weat her be open t he pl ant i ng may cont i nue t hr ough t he

wi nt er . I t hi nk gener al l y t hat ni ne good st r ong heal t hy

pl ant s i n each l i neal yar d, t hat i s, a si ngl e r ow of

qui cks pl aced f our i nches apar t , wi l l f or m an exel l ent

hedge ; al t hough i n some cases t wo r ows ar c pl ant ed.

cont ai ni ng t oget her ei ght een pl ant s i n each yar d. The

pl ant s shoul d be of not l ess t han t hr ee year s' gr owt h,

whi ch wi l l al l ow t hem t o have been t wo year s i n t he

nur ser y- gr ound af t er bei ng t r anspl ant ed f r om t he seed-

l i ngs- bed. The moul d shoul d be of t he bes, t qual i t y,

and shoul d be pl aced i n t he bank t o t he dept h of at

l east t wo f eet , i n or der t hat t he r oot s of t he qui ckset s

Page 16 of 103

may have suf i i ci ent r oom t o st r i ke. The ki nd of soi l

most sui t abl e f or qui ckset s i s t hat of a l i ght sandy or

gr avel l y nat ur e ; and i f i t coul d be sl i ght l y mi xed wi t h

peat woul d be much i mpr oved. A st i f f cl ayey soi l i s

deci dedl y bad ; because i n summer i t becomes har d and

dr y, and i n t hi s st at e t he smal l er f i br es whi ch f eed t he

pl ant cannot penet r at e i nt o i t , and t he qui cks conse-

quent l y di e f or want of sust enance. I n wi nt er t he

f r ost wi l l penet r at e ver y much i nt o cl ayey soi l , and not

onl y ar e t he pl ant s dest r oyed by i t s expansi on and con-

t r act i on, but al so by t he excessi ve col dness of t hi s ki nd

of ear t h. Agai n, i f t he soi l be ver y l i ght and por ous t he

bed becomes t oo dr y i n summer t o af f or d nour i shment t o

t he pl ant s ; but I never knew^ a qui ckset hedge pl ant ed

i n a sandy or l i ght gr avel l y soi l i nj ur ed t hr ough t he

wi nt er . Hence t he onl y pr ecaut i on necessar y i n such

a soi l i s, t o pr event t he dest r uct i ve ef l ect s of t he dr y

summer weat her ; and t hi s I am convi nced woul d be

most ef l ' ect ual l y done i f t he ear t h coul d have a por t i on

of l i ght sl i my peat mi xed wi t h i t . T may ment i on, t hat

t he most heal t hy and l uxur i ant qui ckset hedges I have

ever wi t nessed, ar e pl ant ed i n a moul d of t hi s de-

scr i pt i on. The qui ckset s, i f pr oper l y pl ant ed and wel l

cl eaned and weeded t wi ce a year , ought t o gr ow up

i nt o a t ol er abl e hedge i n about t hr ee year s ; al t hough

t o pr event i t f r om bei ng br oken t hr ough t oo soon, i t

j uay be advi sabl e t o al l ow t he post and r ui l - l ence t o

r emai n as an addi t i onal pr ot ect i on f or f i ve or si x year s ;

23

unt i l i n f act t he t i mber becomes wor n out and de-

st r oyed, whi ch i t usual l y i s by t hat t i me-

Some hedges, however , r equi r e a much l onger t i me

t o acqui r e anyt hi ng l i ke t he st r engt h of a f ence ; but

i n such cases t he f ai l ur e i s usual l y at t r i but abl e t o i m-

pr oper management and unsui t abl e soi l . A l ong t ough

descr i pt i on of couch gr ass, wi t h st r ong r oot s, i s ver y

apt t o gr ow up wi t h t he young shoot s; and unl ess t hi s

enemy be car ef ul l y dest r oyed, at l east t wi ce a year , i t

i s i n vai n t o expect t he qui cks t o acqui r e a heal t hy

gr owt h. But pr obabl y t he most ext ensi ve ki nd of

dest r uct i on i s t hat occasi oned by t he cal ves and sheep

passi ng al ong t he r oad, or past ur i ng i n t he adj oi ni ng

f i el ds. These ani mal s, and par t i cul ar l y t he sheep, ar e

r emar kabl y f ond of t he gr een j ui cy heads of t he young

shoot s, whi ch t hey bi t e of f whenever t hey can r each

t hem ; and t hi s pr act i ce al one, i f al l owed t o cont i nue, ,

wi l l al ways pr event t he qui ckset s exposed t o i t f r om

at t ai ni ng t hei r pr oper si ze and st r engt h. The met hod

of guar di ng agai nst t hi s sour ce of i nj ur y, i s obvi ousl y

t o pl ace t he post and r ai l - f ence at such a di st ance

f r om t he qui ckset s, as t o make t he l at t er beyond t he

r each of t he sheep and cal ves whi ch ar e i n t he habi t

of t hr ust i ng t hei r heads t hr ough t he openi ngs bet ween

t he r ai l s, i n or der t o obt ai n t hi s ver y f avour i t e ki nd of

f ood. For want of at t ent i on t o t hi s pr ecaut i on, many

hedges, whi ch woul d pr obabl y have f or med ver y f i ne

f ences, have t o t hi s day pr oduced not hi ng but st unt ed

i mper f ect shoot s, t hus of cour se ent i r el y f ai l i ng t o r eal i ze

al l expect at i ons of ever gr owi ng up. I n many r oad speci -

f i cat i ons t he di r ect i ons t o t he cont r act or have been, t o

Page 17 of 103

pl ace t he post and r ai l - f ence so near t o t he qui ckset s,

t hat t hey must i nf al l i bl y be dest r oyed f r om t he cause I

have ment i oned ; and t he r esul t has been, i n al most al l

such cases, t hat t he at t empt t o pr ocur e a good f ence

has ent i r el y l ai l ed.

24

CHAPTER I I I .

On t he I mpr ovement of Roads by means of pi t chi ng t he

Bot t om wi t h St ones pl aced on Edge, as adopt ed by^

Mr . Tel f or d on t he London and Hol yhead Road.

I n t hose di st r i ct s wher e gr ani t e or t he ol der st r at i -

f i ed r ocks pr evai l , t he r oadmaker possesses t he advan-

t age of havi ng at command t he ver y best possi bl e

mat er i al s f or const r uct i ng a per f ect l y har d and sol i d

r oad. So hi ghl y has gr ani t e been pr i zed as a cover i ng

f or r oads i n t he nei ghbour hood of t he met r opol i s, on

whi ch of cour se i mmense t r af f i c exi st s, t hat t hi s mat e-

r i al has been pr ocur ed f r om t he i sl and of Guer nsey,

f r om Dar t moor f or est i n Devonshi r e, and ot her pl aces,

at an expense of not l ess t hat a gui nea per t on. Of al l

t he gr ani t es ever used as a r oad- cover i ng, t he Guer nsey

i s est eemed t he best ; and f r om a ser i es of exper i ment s

made under t he di r ect i on of Mr . Wal ker , Pr esi dent of

t he I nst i t ut i on of Ci vi l Engi neer s, i t appear s, t hat t he

wear of di f f er ent ki nds of gr ani t e i s i n t he f ol l owi ng

or der : Guer nsey, Her m, Pet er head ( bl ue) , Heyt or ,

Aber deen ( r ed) , Dar t moor , Aber deen ( bl ue. )

The gr and di st i nct i on bet ween t he gr ani t e and l i me-

st one r ocks, even of t he har dest cl ass, i s, t hat t he f or mer

ar e f ar mor e capabl e t han t he l at t er of r esi st i ng di si n-

t egr at i on by t he act i on of wat er and f r ost ; and as

t hey possess i n an emi nent degr ee t he qual i t i es of har d-

ness and dur abi l i t y, t hey may saf el y be used, ei t her i n

t he shape of bl ocks t o f or m t he f oundat i on of t he r oad,

or , whci i br oken t o a sui t abl e si ze, may be appl i ed as a

25

t op cover i ng wi t h whi ch t he wheel s ar e t o be i n i mme-

di at e cont act . I f t he bed of a r oad, af t er bei ng made

per f ect l y dr y, be cover ed over wi t h a l ayer of br oken

gr ani t e, t he angul ar shape of t he st ones wi l l al l ow t hem

t o wedge and dovet ai l as i t wer e i nt o each ot her , so

t hat w hen pr essed by t he wheel s r ol l i ng over t hem, t he

whol e wi l l f or m a sol i d r esi st i ng mass of gr eat st abi -

l i t y and har dness. Hence, al t hough I woul d r ecom-

mend t hat a r egul ar f oundat i on made i n t he manner

her eaf t er descr i bed, be l ai d down i n al l r oads wher e

anyt hi ng l i ke ext ensi ve t r af f i c i s t o be car r i ed on, yet i f

i t wer e asked i n what case t hi s f oundat i on mi ght wi t h

t he l east i nj ur y be di spensed wi t h, I shoul d answer , i n

t hat si t uat i on wher e t he r oad met al consi st s of br oken

gr ani t e. I n no ot her case t han t hi s, however , shoul d t he

Page 18 of 103

gener al r ul e on any account be depar t ed f r om, of con-

st r uct i ng a sol i d ar t i f i ci al f oundat i on bef or e l ayi ng on

t he t op cover i ng. Even on t he scor e of economy, t he

r oad pi t chi ng shoul d be adopt ed i n pr ef er ence t o t he

br oken st one met al l i ng, because i t wi l l be f ound cheaper

t o pi t ch t he r oad wi t h har d st ones t han t o br eak t hem

up f or a r oad cover i ng.

Two di st i nct ki nds of r oad f oundat i on wi l l be de-

scr i bed i n t he f ol l owi ng chapt er s, namel y

f i r st , t he

pi t ched bot t om f oundat i on ment i oned above, whi ch was

i nt r oduced by Mr . Tel f or d, and whi ch consi st s of a

cl ose f i r m pavement of st ones, pl aced si de by si de on

t hei r br oadest base ; and next , t he concr et e f oundat i on,

composed of gr avel or br oken st one, mi xed i r i pr oper

pr opor t i ons wi t h l i me or cement . The f or mer of t hese

t wo ki nds wi l l be appl i cabl e t o t hose di st r i ct s wher e, i n

pl ace of gr ani t e and whi n, t he st r at i f i ed r ocks of l i me-

st one and sandst one pr evai l

t o ever y si t uat i on, i n

f act , wher e any descr i pt i on of st one can be pr ocur ed

at a r easonabl e pr i ce.

26

Al t hough some ki nds of sandst one ar e t ol er abl y

har d, t he pr evai l i ng char act er i st i c i s t hat of a dr y

br i t t l e r ock, easi l y br oken and easi l y gr ound t o powder ,

t her ef or e gener al l y ver y unf i t f or t he pur pose of a r oad

cover i ng. Al l ki nds of l i mest one ar e st i l l mor e i nappl i -

cabl e as a t op coat i ng t han sandst one. I t has of t en

been obser ved, t hat i n dr y weat her l i mest one f or ms an

excel l ent r oad; but owi ng t o t he capaci t y of t hi s mat e-

r i al f or wat er , t he sl i ght est r ai n pr oduces an al most

i nst ant aneous ef f ect on t hi s ki nd of r oad. A sur f ace,

whi ch i n dr y weat her i s, per haps, per f ect l y har d and

smoot h, becomes af t er a shower of r ai n a compl et e

puddl e: t he wat er r ender s t he st one qui t e sof t , and i n

t hi s st at e i t i s soon gr ound i nt o mud. Wher e t her e i s

much t r af f i c, a ver y shor t cont i nuance of Avet weat her

wi l l compl et e t he dest r uct i on of a coat i ng si x or ei ght

i nches i n t hi ckness, whi ch under t hese ci r cumst ances

wi l l be cut t hr ough by t he wheel s i n a mar vel l ousl y

shor t space of t i me. I f t he mud be not i mmedi at el y

scr aped away, i t becomes ver y cl ammy i n t he pr ocess

of dr yi ng, and i n t hi s st at e t he r oad nat ur al l y r equi r es a

ver y heavy power of dr aught . I n dr y weat her t he mud

f or med dur i ng wet seasons becomes dust ; and i n r oads

of t hi s ki nd i t usual l y exi st s t o an ext ent ser i ousl y an-

noyi ng t o t he unf or t unat e t r avel l er s, who somet i mes

can har dl y escape bei ng smot her ed.

Shoul d a f r ost occur t he l i mest one r oad wi l l suf f er

much mor e t han f r om t he r ai n

t he moi st ur e whi ch t hi s

ki nd of st one so copi ousl y i mbi bes, wi l l be expanded

by t he act i on of t he f r ost t o a l ar ger bul k t han when i n

t he l i qui d f or m ; and t he consequence of t hi s i s an i m-

ni edi at e shat t er i ng and bur st i ng of t he st one, whi ch i n

many cases i s al most r educed t o powder , or at any

r at e i s r ender ed capabl e of bei ng cr ushed by t he f i r st

wheel wi i i ch may pass over i t . As soon as t he sun

Page 19 of 103

27

begi ns t o mel t t he f r ost , t he l i mest one cover i ng becomes

t en t i mes mor e adhesi ve t han ever : i t may now wi t h

t r ut h be compar ed t o bi r dl i me, so t enaci ousl y i t adher es

t o t he wheel s of t he car r i ages. The wor k of dest r uc -

t i on becomes r api d and ast oni shi ng i n i t s ef f ect s ; t he

whol e r oad i s t or n t o pi eces, i mmense pat ches of t he

cover i ng ar e ent i r el y st r i pped f r om t he sur f ace, and t he

r oad deepl y i ndent ed wi t h l ar ge hol l ows. Such ar e t he

ef f ect s pr oduced even on t he best ki nd of l i mest one

r oad by a f ew ni ght s of sl i ght f r ost , succeeded by t he

f i ne sunny mor ni ngs of aut umn and some of t he mi l d

wi nt er s. Upon t he whol e, t he obj ect i ons t o l i mest one

ar e so numer ous and so wel l f ounded, t hat t hi s mat er i al

shoul d never i n any si t uat i on be used as an upper

cover i ng, or r oad met al l i ng.

I n condemni ng t he use of br oken l i me and sandst one

as an upper cover i ng, I woul d however except t he har d

var i et i es of t he l at t er whi ch cont ai n i r on. Sandst one

of t hi s ki nd, f ound i n t he gr een sand r anges of Sur r ey

and Sussex, i s ext ensi vel y appl i ed on t he nei ghbour i ng

r oads, wher e t he sur f ace f or med by t hi s ki nd of st one i s

ext r emel y har d, and i ndi cat es a ver y smal l amount of

f r i ct i on. On a par t of t he Sur r ey and Sussex r oad, i n

t he nei ghbour hood of Red Hi l l , I have been f or ci bl y

st r uck wi t h t he excel l ent sur f ace f or med by t hi s ki nd

of st one. Al t hough not i n possessi on of any act ual

exper i ment on t he amount of f r i ct i on, yet f r om havi ng

passed over i t a gr eat number of t i mes, and f r om ob-

ser vi ng t he ease and speed wi t h whi ch hor ses dr awi ng

car r i ages, coaches, and gi gs, ar e abl e t o ascend hi l l s of

consi der abl e accl i vi t y on whi ch t hi s st one has been l ai d

down, I shoul d vent ur e t o pr edi ct , t hat t he f r i ct i on i s

not mor e t han on t he best gr ani t e r oad I ever saw. The

same ki nd of i r on sandst one i s f ound at Pul bor ough,

and ot her par t s of t he sand r ange under l yi ng t he Sout h

28

Down chal k hi l l s ; and t her e al so i t has been ext en-

si vel y used as a r oad mat er i al , par t i cul ar l y bet ween

Pul bor ough and Bi l l i nghur st , a par t of t he r oad acknow-

l edged, by t he coachmen and ot her s acquai nt ed wi t h i t ^

t o be t he best bet ween London and Ar undel .

Whi l st , however , no doubt can be ent er t ai ned of t he

gener al unf i t ness of l i mest one and t he sof t er ki nds of

sandst one f or t he upper cover i ng of a r oad, we ar e i n-

debt ed t o t he l at e Mr . Tel f or d f or t he knowl edge of a

most admi r abl e appl i cat i on of t hese ki nds of st one t o

t he pur poses of r oadmaki ng. Pr oceedi ng on t he pr i n-

ci pl e, t hat next t o t he ef f i ci ent and t hor ough dr ai nage

of a r oad, t he secur i ng a good, har d, f i r m f oundat i on i s

t he most i mpor t ant obj ect t o be at t ended t o, t hat

emi nent engi neer di r ect s, i n hi s speci f i cat i ons f or wor ks

on t he London and Hol yhead r oad, t hat " upon t he

new sur f ace or l evel space pr epar ed f or t he r oad mat e-

r i al , a f oundat i on of l i mest one, sand, or mar l st one i s t o

be l ai d i n t he f or m of a cl ose f i r m pavement . The

Page 20 of 103

dept h of each st one i s t o be seven i nches i n t he mi ddl e

of t he r oad, and f i ve i nches at t he si des ; t he st ones ar e

t o be set l engt hwi se acr oss t he r oad, t hey ar e t o be

l ai d on t hei r br oadest edge, and t he br eadt h of t he upper

edge i s i n no case t o exceed f our i nches; al l t he i n-

equal i t i es i n t he upper par t of t he pavement ar e t o be

br oken of f wi t h t he hammer , and al l t he i nt er st i ces f i l l ed

wi t h st one chi ps, f i r ml y wedged or packed by hand and

a l i ght hammer , so as t o f or m a r egul ar convexi t y of

one i nch i n ni ne f eet f r om t he cent r e, and t hr ee i nches

at t he channel s, or at t he di st ance of f i f t een f eet f r om

t he cent r e. "

The ki nd of pi t chi ng her e descr i bed consi st ed of

sand and l i mest one, whi ch woul d have been qui t e i nap-

pl i cabl e as a t op coat i ng f or t he r oad; but whi ch was

f ound, when cover ed by a l ayer of gr avel or har d br oken

29

st one, t o f or m a most excel l ent r oad. I t i s t r ue, t hat

when t hi s met hod of r oad pi t chi ng was f i r st adopt ed,

t he opi ni ons of sever al sci ent i f i c engi neer s wer e op-

posed t o i t ; but t he super i or i t y i t possesses over t he

or di nar y mode of l ayi ng on t he gr avel or br oken st one

i n a body, has now become so evi dent , t hat f ew per sons

ar e any l onger di sposed t o doubt t he mer i t of i t s i nt r o-

duct i on i nt o t he pr act i ce of r oadmaki ng.

Sur veyor s, t her ef or e, i n t hose di st r i ct s whi ch do not

pr oduce t he har der ki nds of r ock, have, i n t he way de-

scr i bed, an oppor t uni t y of empl oyi ng t o gr eat advan-

t age t he i nf er i or descr i pt i ons of st one, whi ch ar e ver y

commonl y f ound al l over Engl and. The adopt i on of

t hi s met hod i s r ecommended by numer ous consi der a-

t i ons, mor e especi al l y t o al l t hose par i shes whi ch ar e

bur dened by a l ar ge number of pauper s. The st one t o

be used f or t he pi t chi ng, af t er bei ng quar r i ed, r equi r es

ver y l i t t l e br eaki ng; because sandst one, and t he upper

or l ess val uabl e beds of l i mest one, ar e gener al l y quar r i ed

as wast e or spar e r ubbl e, i n pi eces of about t he pr oper

si ze f or r oad pi t chi ng; and most quar r i es pr oduce mor e

of t hi s st uf f t han can be wor ked up i n any bui l di ng.

The pr i ce of t hi s ki nd of st one at some quar r i es i s t hr ee-

pence a car t - l oad ; and I never knew mor e t han si x-

pence char ged. I n some pl aces, however , wher e t he

quar r y has t o be newl y opened, i t may cost a shi l l i ng

per cube yar d; but i f t he quar r y be si t uat ed on a

common or wast e pi ece of l and, t he st one cost s t he

par i sh not hi ng but t he l abour of t he wor kmen.

The pr i nci pal expense t hen, besi des t hat of car t i ng

f r om t he quar r y t o t he r oad, i s t he l abour of pi t chi ng t he

st ones by hand ; and t he ar t of per f or mi ng t hi s ki nd of

wor k wi t h neat ness and expedi t i on i s ver y soon l ear ned

by a l abour er of or di nar y capaci t y. The pr i ce usual l y

30

pai d f or t he act ual l abour of l ayi ng down t he pi t chi ng

Page 21 of 103

on t he Hol yhead r oad, i s f r om one shi l l i ng t o f our t een

pence per l i neal yar d of 30 f eet wi de ; and a wor kman

of t ol er abl e i ndust r y can wi t h ease l ay down about f our

yar ds i n l engt h per day.

The pr act i ce of f or mi ng a pi t ched f oundat i on, as

descr i bed i n t he pr ecedi ng ext r act f r om one of Mr . Tel -

f or d' s speci f i cat i ons, havi ng been empl oyed wi t h gr eat

success i n most of t he i mpr ovement s execut ed on t he

Hol yhead r oad, has t hus r ecei ved t he val uabl e sanc-

t i on of pr act i cal exper i ence ; and may saf el y be r ecom-

mended as an ef f ect ual cur e f or t hose t r oubl esome cases

i n r oadmaki ng, wher e t he st r at um composi ng t he bed

of t he r oad di spl ays a t endency t o bur st t hr ough and

mi x wi t h t he r oad mat er i al s. I t i s vai n t o ar gue, t hat a

gr eat body of gr avel or br oken st one wi l l of i t sel f

pr ove suf f i ci ent t o pr event t he sub- soi l f r om r i si ng.

To t hose who adopt an i dea so er r oneous, I woul d

si mpl y obser ve, t hat t hey can never have been ac-

quai nt ed wi t h any ver y di f f i cul t cases of t hi s ki nd. I

have mysel f , i n br eaki ng up ol d r oads, f ound l ayer upon

l ayer of excel l ent gr avel t o t he dept h somet i mes of not

l ess t han f our f eet , but compl et el y mi xed wi t h t he

cl ayey mat er i al whi ch had f ound i t s way f r om beneat h.

Wher e a r oad happened t o be car r i ed over t hi s ki nd of

mat er i al , and i t was f ound t o mi x wi t h t he gr avel whi ch

f or med t he cover i ng of t he r oad, t he ol d syst em, f or t he

most par t , r ecogni zed no ot her pr act i ce of st oppi ng t he

evi l t han t hat of l oadi ng t he r oad wi t h a f ur t her quan-

t i t y of gr avel or br oken st one

an appl i cat i on whi cl i

pr oved of an ext r emel y t empor i zi ng and i mper f ect

char act er ; because no sooner had one l ayer of gr avel

become mi xed wi t h t he sub- soi l , t han t he l at t er r ose

i nt o t he coat i ng l ast put on, and t l i c whol e mass of r oad

31

t i i at er i al became r educed t o t he same cl ogged and spongy

condi t i on as bef or e t he appl i cat i on of t he new gr avel .

I n al l obst i nat e cases of t hi s ki nd, however , t he pi t ched

f oundat i on wi l l most ef f ect ual l y pr event any r i si ng of

t he sub- soi l , and t he gr avel l ai d on as an upper coat i ng

wi l l t hen have a f ai r chance of bi ndi ng and becomi ng

suf f i ci ent l y har d and sol i d t o f or m a good t r avel l i ng

sur f ace.

I n t he f ol l owi ng chapt er wi l l be f ound some account

of t he met hod r esor t ed t o f or t he i mpr ovement of t he

Hi ghgat e Ar chway Road, af t er i t was pl aced under t he

management of Mr . Tel f or d. I had i n t hat case act ual

and ocul ar demonst r at i on, t hat t he var i ous pr ocesses

of l ayi ng br ushwood and t i n chi ppi ngs i n t he bed of t he

r oad had pr evi ousl y been adopt ed ; and i n many ot her

cases, I have seen t he r emai ns of f agot s whi ch had

been i nt er posed bet ween t he upper coat i ng of gr avel

and t he sub- soi l , whi ch i t was vai nl y ant i ci pat ed woul d

i n t hi s way be pr event ed f r om r i si ng. I t woul d seem

t hat t hose ol d r oadmaker s, who have so t or t ur ed t hei r

i nvent i ve f acul t i es t o devi se means f or secur i ng a f i r m

f oundat i on f or t he upper coat i ng of t he r oad, woul d

har dl y agr ee t o some of t he axi oms l ai d down by a

moder n r oad sur veyor of emi nence, whose name, wi t h

Page 22 of 103

an appr opr i at e t er mi nat i on, has been i nt r oduced i nt o

t he Engl i sh l anguage t o di st i ngui sh t he syst em of r oad-

maki ng of whi ch he i s t he aut hor . Accor di ng t o t hi s

gent l eman, " i t i s no mat t er whet her t he sub- st r at um of

a r oad be har d or sof t . " The advocat e of a doct r i ne so

het er odox mi ght der i ve an usef ul l esson f r om t he expe-

r i ence of t hose ol d r oadmaker s, who wer e evi dent l y at

so much pai ns t o cor r ect and obvi at e t he mi sf or t une of

a sof t sub- st r at um. I can scar cel y hel p t hi nki ng, t hat

such a doct r i ne coul d onl y have or i gi nat ed f r om a ver y

32

super f i ci al acquai nt ance even wi t h t he exi st i ng con-

di t i on of r oads. To most per sons i n t he habi t of pr ac -

t i si ng anyt hi ng l i ke obser vat i on as t hey pass t hr ough

l i f e, t her e ar e f ew di f f er ences mor e st r i ki ng t han t hat

bet ween a r oad f or med on a sof t f oundat i on, and one

whi ch has t he advant age t o pass over a har d sub-

st r at um.

The gr eat pr i nci pl e of ut i l i t y i s st r i ki ngl y consul t ed

i n Mr . Tel f or d' s pr act i ce of pi t chi ng t he f oundat i on of

t he r oad; f or i t must be bor ne i n mi nd, t hat t he mat e-

r i al s t o be used f or t hi s pur pose woul d f or t he most

par t be ut t er l y usel ess f or a t op cover i ng, and yet when

empl oyed as a pi t chi ng i n t he way bef or e descr i bed, an

ext r emel y dur abl e and excel l ent r oad i s t he r esul t . I f

r oad sur veyor s coul d onl y be pr evai l ed on t o adopt t he

syst em of pi t chi ng t hei r r oads wi t h such mat er i al s as

ar e f ound pr et t y gener al l y t hr oughout t hi s count r y, I

am cer t ai n t hey woul d soon f i nd, i n t he super i or char ac -

t er of t he r oads t hey woul d be enabl ed t o f or m, ampl e

cause t o congr at ul at e t hemsel ves on havi ng st epped

asi de f r om t he ol d pr act i ce of l oadi ng t he r oad wi t h

enor mous quant i t i es of gr avel or br oken st one.

I n consi der i ng t he qual i t y of st one pr oper f or t he

pur poses of r oad pi t chi ng, i t i s an er r or t o suppose t hat

none but ver y har d st one shoul d be used. The sof t

ki nds of sandst one and f r eest one, and ver y i nf er i or ki nds

of l i mest one, have been ext ensi vel y used on t he Hol y -

head r oad ; and I am per suaded t hat bl ocks of chal k,

par t i cul ar l y of t he ki nd cal l ed r ock- chal k, woul d f or m

a ver y excel l ent mat er i al f or pi t chi ng. I n any case,

however , wher e chal k or even l i mest one i s used f or

pi t chi ng, t he dr ai nage of t he r oad becomes of mor e t han

or di nar y i mpor t ance. I n or der t o pr eser ve t hi s mat e-

r i al , i t i s absol ut el y necessar y t o pr ot ect i t f r om t he

33

at mospher e, whence i t woul d ot her wi se i mbi be moi st ur e

whi ch woul d shor t l y pr oduce ver y dest r uct i ve ef l ect s ;

and t he pr ecaut i on of pr ot ect i ng t he pi t chi ng f r om t he

ai r wi l l evi dent l y be ent i r el y usel ess, unl ess t he bed of

t he r oad be f i r st made per f ect l y dr y ; but i f t hi s dut y be

ef t ect ual l y at t ended t o, chal k i t sel f , and t he sof t er ki nds

of l i mest one r ock, wi l l r esi st t he pr ogr ess of decay f or

a ver y l ong t i me.

Page 23 of 103

34

CHAPTER I V.

On t he I mpr ovement of t he Hi ghgat c Ar chi vay Roady

by means of a Concr et e Foundat i on, composed of

Gr avel and Cement .

The f i r st ef f ect ual met hod adopt ed f or t he i mpr ove-

ment of t hi s r oad, was execut ed under Mr . Tel f or d' s

di r ect i ons i n t he year 1828 ; and f or some t i me t he

new ki nd of f oundat i on t hen i nt r oduced, consi st ed of

moul ded br i cks f or med of gr avel and Par ker ' s cement .

The pr ocess of maki ng and l ayi ng t hese concr et e br i cks

was however f ound t o be ver y expensi ve, and many

pr act i cal di f f i cul t i es at t ended t hei r use. I t was i mpos -

si bl e t o pr event t hem f r om br eaki ng and f al l i ng t o pi eces

when t aken out of t he moul ds, and f r om cr umbl i ng and

br eaki ng when pl aced i n t he heaps t o under go t he pr o-

cess of dr yi ng; whi l st many ot her s, whi ch had up t o

t hat t i me r emai ned whol e, wer e br oken t o pi eces i n t he

act of r emoval by car t s, al t hough t hi s oper at i on was

per f or med wi t h t he ut most car e, and st r aw pl aced be-

t ween each cour se t o pr event br eakage. I n t hi s way I

am qui t e saf e i n asser t i ng, t hat at l east one- t hi r d of t he

whol e quant i t y of moul ded br i cks wer e l ost . I n conse-

quence of t hese numer ous obj ect i ons, t he pr act i ce of

usi ng t he br i cks was at r ay suggest i on event ual l y

abandoned, Mr . Tel f or d di r ect i ng t hat t he concr et e

shoul d be l ai d i n mass wi t hout bei ng moul ded i nt o t l i e

f or m of br i cks ; and f r om t hi s per i od t he mi xt ur e w as

made up i n a wooden t r ough on t he gr ound, and t hen

car ef ul l y pl aced i n t he bed of t he r oad ; and bef or e i t

35

was al l owed t o get har d, a wooden moul d shaped t huSj

l i ke t he l et t er V, was st amped t r ansver sel y at t he di s -

t ance of ever y f oot apar t , i n or der t o al l ow any wat er

t o dr ai n down t hi s i ndent ed channel i nt o t he si de dr ai n,

and al so, t hat t he cover i ng of st one or gr avel mi ght mor e

easi l y bi nd and become sol i d on t he concr et e. Thi s

met hod, al t hough a gr eat i mpr ovement on t he f i r st pl an,

was ver y expensi ve and t edi ous, pr i nci pal l y on account

of t hat pr oper t y i n t he cement by r eason of whi ch i t

set s and becomes har d, i n a r emar kabl y shor t t i me af t er

bei ng f or med i nt o concr et e

a pr oper t y whi ch r ender ed

i t necessar y t hat onl y a ver y smal l quant i t y shoul d be

pr epar ed and l ai d at one t i me.

The f ol l owi ng shor t st at ement shows t he pr opor -

t i ons of gr avel and cement used f or t he concr et e :

One bushel of cement made 30 br i cks = 5 cube f eet .

One bar r el of cement made 150 br i cks = 25 do.

The bushel cont ai ns 2218 cube i nches ; and 30 br i cks

Page 24 of 103

cont ai n 8640 cube i nches, l eavi ng 6422 cube i nches of

gr avel . Hence t he pr opor t i on of cement t o gr avel i s

t hat of 2218 : 6422, or as 22 t o 64, or i n r ound number s

about 1 of cement t o 3 of gr avel .

Al t hough on account of t he br eakage and l oss sus -

t ai ned, I am not i n possessi on of suf f i ci ent dat a t o

det er mi ne wi t h accur acy t he cost of pi t chi ng t he r oad

wi t h br i cks, t he f ol l owi ng est i mat e of t he act ual ex -

pense of f or mi ng t he concr et e bot t om wi l l f ur ni sh some

i dea of t he i ncr eased expense whi ch must have at t ended

t he use of t he br i cks.

Four men mi xed and l ai d about 8 l i neal yar ds of

concr et e, 7 f eet 6 i nches wi de and 6 i nches deep

t hi s

bei ng equal t o 8 yar ds x 2| x 0. 166 yar ds = ; ] | cube

yar ds : t her ef or e 12 men woul d l ay 10 cube yar ds of

concr et e per day. And di vi di ng t hi s quant i t y i n t he

D 2

36

r at i o of 11 t o 32, we f i nd t hat 12 men woul d use per day

50 bushel s of cement and 7. 44 cube yar ds of gr avel .

Hence t he f ol l owi ng est i mat e :

s. d.

Cement , 50 bushel s, at ^ s. . . . 5

( i r avel , * 7. 44 cube yar ds, at 8s. . . 2 19 6

Labour er s, 12 men, at 3 . . . . 1 16

Cost of 10 yar ds cube, or 12 l i neal yar ds, " ] ~

15 f eet wi de, /

Fr om t hi s we see t hat t he cost of t he concr et e was

19^ . ( yd. per cube yar d, or 16s. 3( Z. per l i neal yar d of

15 f eet wi de. I t shoul d be not i ced, i n det ai l i ng t he

pr i ce of t he gr avel at 8s. per cube yar d, t hat t he unf a-

vour abl e ci r cumst ances i n whi ch t he wor k at Hi f f hsr at e

was pl aced, wi t h r ef er ence t o t he suppl y of gr avel , wer e

cer t ai nl y r at her unusual . Thi s mat er i al coul d onl y be

obt ai ned at a consi der abl e di st ance f r om t he wor ks; and

when dug r equi r ed gr eat car e t o be t aken i n t he wash-

i ng and scr eeni ng, i n or der t o r ender i t per f ect l y devoi d

of ear t hy mat t er bef or e mi xi ng i t i n t he concr et e

t he

consequence was, t hat none of t he gr avel used i n t he

Hi ghgat e Ar chway r oad cost l ess per yar d t han t he

sum ment i oned i n t he pr ecedi ng est i mat e.

I t may not be i r r el evant t o st at e her e, t hat t he Ar ch-

way r oad, t o whi ch t hi s descr i pt i on of t he wor k

r el at es, was, at t he t i me when i t came under t he super -

i nt endence of Mr . Tel f or d, pr obabl y one of t he wor st

pi eces of r oad i n t he ki ngdom ; and, not wi t hst andi ng

t he consul t at i ons of engi neer s and ot her sci ent i f i c men

whi ch had f r equent l y t aken pl ace, and t he var i ous

Page 25 of 103

at t empt s whi ch had been made by t hem t o r ender t hi s a

* Gr avel at Hi ^ ^ hgat e, car t ed f r om t he Thames, i ncl i ul i nj i f t ol l s,

&c. woul d not cost l ess t han i s her e st at ed;

i f f r om Fi uchl ey, or

t hat nei ghhour hood, t he car t i ng- , wast e, and washi ng t o r ender i t f i t

t o mi x wi t h cement , made i t equal l y expensi ve.

37

good t r avel l i ng r oad, ever y at t empt and t r i al , al t hough

at t ended by t he expendi t ur e of " many t housand pounds,

and al most by t he i nsol vency of t he Hi ghgat e Ar chway

Company, was f ound t o be i nef f ect ual i n pr oduci ng

anyt hi ng l i ke a per manent i mpr ovement i n t he condi t i on

of t he r oad. These var i ous at t empt s, i n f act , wer e

di ct at ed by such r emar kabl e i gnor ance of pr act i cal

pr i nci pl es, t hat i nst ead of di mi ni shi ng or r emovi ng, i t

has been supposed t hey act ual l y ended by i ncr easi ng

t he evi l . The geol ogi cal st r at a composi ng t he hi l l

t hr ough whi ch t he r oad i s car r i ed, ar e t hose of t he

London Cl ay Basi n: t hey cont ai n a consi der abl e

mi xt ur e of sand and gr avel , whi ch bei ng per meabl e

mat er i al s, ar e consequent l y f ul l of wat er . No syst e-

mat i c f or m of dr ai ni ng had ever been consi der ed by t he

sci ent i f i c men who wer e consul t ed ; and as t he conse-

quence of t hi s negl ect t hr oughout t he wi nt er , and i n al l

wet seasons, spr i ngs of wat er wer e numer ous, not onl y

i n t he si des of t he excavat i ons but even i n t he mi ddl e

of t he r oad. I t f ol l owed, t her ef or e, t hat any dept h of

cover i ng i nt ended t o keep t he under st r at um f r om r i si ng

amongst t he gr avel or har d mat er i al pr oved qui t e i nef -

f ect ual ; f or as f ast as new mat er i al s wer e l ai d on t hey

wer e pr essed i nt o t he sof t bot t om, and mud, cl ay, and

sand suppl i ed t hei r pl aces. I t has been consi der ed,

and wi t h gr eat t r ut h, t hat t hi s pi ece of r oad has occa-

si oned mor e l oss t o coach- hor se pr opr i et or s t han any

ot her of t he same ext ent ei t her i n t hi s or i n any ot her

count r y.

The f i r st det er mi nat i on f or med by t he aut hor i t i es of

t he day, af t er an exami nat i on of t he r oad and al l t l i e

causes of i t s def ect s, was t o have t he exi st i ng sur f ace

t aken ent i r el y out

t he whol e bed was t o be t hen cover ed

wi t h br ushwood f agot s, and t hi s agai n t o be cover ed over

wi t h a good and suf i i ci ent coat i ng of excel l ent cl ean

38

gr avel . That t hi s was f ar f r om bei ng a cheap exper i -

ment I need har dl y say, whet her i t wer e a good one had

t hen t o be t r i ed. The r esul t nat ur al l y f ol l owed, whi ch

any pr act i cal man woul d have f or eseen

t he r oad, whi l st

t he gr avel was l oose and t he br ushwood not compr essed,

was per f ect l y dr y on t he sur f ace ; but i n consequence

of t he gr eat dept h of l oose gr avel and t he el ast i c nat ur e

of t he br ushwood f oundat i on, not hi ng i n my opi ni on

coul d have been bet t er devi sed f or t he dest r uct i on of

hor ses t han t hi s t r ul y i nf amous pi ece of r oad. * Thi s

was t he st at e of t hi ngs when t he r oad r emai ned un-

bound ; but as soon as by compr essi on t he f agot s wer e

Page 26 of 103

near l y r ot t en and made sol i d, and when i t was expect ed

t hat t he gr avel woul d bi nd and a sol i d sur f ace be

f or med, i nst ead of t hi s t he gr avel was al l near l y gr ound

t o dust : and cer t ai nl y out of t he expensi ve mat er i al s

l ai d on t he r oad t her e was not hi ng l ef t but coar se gr i t .

Thi s mat er i al , I need har dl y say, was mor e unf i t t o

car r y t he t r at l i c t han t hat whi ch t hey had t aken up t o

make r oom f or i t ; and t he per i shabl e f agot s havi ng now

become r ot t en, t her e was not hi ng t o pr event t he mud

and cl ay f r om mi xi ng wi t h t he upper cover i ng. The

whol e r oad was now t en t i mes wor se t han ever ; and a

mat er i al of a char act er ver y novel i n t he hi st or y of r oad-

maki ng was f i xed upon i n car r yi ng i nt o ef i ect a t hi r d

at t empt t o i mpr ove t he r oad. Thi s was no ot her

t han t he r ef use or wast e chi ppi ngs of t i n ; i n or der t o

make r oom f or whi ch t he ol d sur f ace was agai n t or n up,

and t he whol e bed cover ed wi t h sever al i nches i n dept h

of t he t i n chi ppi ngs

a f act whi ch account ed f or t he

di scover y, when I came t o put i nt o execut i on Mr .

Tel f or d' s pl an of f or mi ng a cement ed bot t om, of sever al

t ons of t hi s mat er i al i n a st at e of par t i al r ust , and i n

* The i ncl i nat i on of t he l i i l l , on wl i i ch t he coaches had t o he

dr agged f ul l y i i al f a mi l e, \ \ as ahout 1 i n oO.

30

some pl aces knot t ed and kneaded i nt o t he cl ay, gr avel ,

and some smal l por t i ons of t he f agot s, whi ch had

pr obabl y not been t aken ent i r el y away. I t hi nk I need

har dl y say t hat , not wi t hst andi ng t he sangui ne expect a-

t i ons of t hose who wer e i nduced t o adopt t he novel

expedi ent of t hus f or mi ng an act ual met al l i c sub- st r at um

f or t he r oad cover i ng t o r est upon, t he pl an I have j ust

descr i bed, al t hough no cheaper t han t hose r esul t i ng

f r om f or mer del i ber at i ons, pr oved as compl et e a f ai l ur e

as any whi ch had pr eceded.

I t i s per f ect l y wel l known, t hat t hi s same Hi ghgat e

Ar chway r oad, whi ch had so per t i naci ousl y r esi st ed al l

exer t i ons t o i mpr ove i t on t he par t of f or mer engi neer s,

became, under t he management of Mr . Tel f or d, one of

t he ver y best r oads i n t he ki ngdom. Mr . M' Nei l , I

bel i eve, showed by means of hi s f r i ct i on- t est i ng ma-

chi ne, t hat t he power r equi r ed f or dr aught on t hi s

r oad was l ess t han on al most any ot her whi ch had been

t r i ed i n t he same way ; and t he super i or i t y t hus i ndi -

cat ed, i s f ul l y conf i r med by t he t est i mony of t he st age-

coachmen and ot her s dr i vi ng over t hi s par t of t he

Hol yhead r oad.

At t he same t i me, however , t hat ever y one at al l

acquai nt ed wi t h t he subj ect i s r eady t o admi t t he ext ent

and i mpor t ance of t he change f or t he bet t er whi ch has

t aken pl ace i n t he condi t i on of t he Ar chway r oad si nce

t he adopt i on of t he cement ed bot t om, i t f ol l ows by no

means as a necessar y consequence, t hat t hi s i mpr ove-

ment i s ent i r el y t he ef f ect of t he par t i cul ar ki nd of f oun-

dat i on or sub- st r at um on whi ch t he r oad mat er i al i s now

l ai d. I n or der t o be convi nced of t hi s, and al so t hat ,

knowi ng al l t he act ual means of i mpr ovement , we may

der i ve t he gr eat est amount of pr act i cal exper i ence, we

Page 27 of 103

must consi der t he mer i t of t he ver y excel l ent dr ai nage

devi sed bv Mr . Tel f or d, and whi ch I bel i eve was on a

40

f ar mor e ext ensi ve scal e, and t her ef or e mor e l i kel y t o

be benef i ci al t han any t hat had been adopt ed by bi s

pr edecessor s i n t he management of t hi s r oad. As i t

may be usef ul t o t he r oad sur veyor gener al l y, t o know

t he syst em of dr ai nage whi ch was at l engt h so ef i ect u-

al l y act ed upon, I shal l not hesi t at e t o descr i be i t i n

det ai l . Al ong t he whol e l engt h, and on each si de of

t he r oad, l ongi t udi nal si de dr ai ns wer e cut , t wo f eet

wi de and f our f eet deep, bel ow t he bed of t he r oad.

Longi t udi nal shoul der dr ai ns, one f oot deep, wer e al so cut

t he whol e l engt h of t he r oad on each si de of t he cement ed

bot t om

t hat i s seven f eet and a hal f on each si de t he

cent r e of t he r oad

and t r ansver se mi t r e dr ai ns, openi ng

i nt o t he shoul der and si de dr ai ns, wer e f or med acr oss t he

r oad at i nt er val s of f r om f i f t een t o t went y - f i ve yar ds. The

deep si de dr ai ns had a t i l e and sough cover f i ve i nches

di amet er l ai d i n t he bot t om, and above t hi s t he dr ai n

was f i l l ed i n ei ght een i nches wi de wi t h cl ean st ones,

t he space of si x i nches bet ween t he si des of t he

dr ai n and t he r oad si de bei ng f i l l ed wi t h cl ay and wel l

pounded. The ot her dr ai ns had no sough or t i l e, but

l i ke t he si de dr ai ns wer e f i l l ed t o t he t op wi t h cl ean

st ones.

I t was t he nat ur al r esul t of a dr ai nage so compl et e

as t hat whi ch I have descr i bed, t hat wat er f al l i ng on

sur f ace of t he r oad coul d not l odge i n t he bot t om, and

i n t hi s way keep t he r oad i n a sof t and wet st at e, but

woul d i mmedi at el y be conveyed i nt o t he shoul der or

si de dr ai ns qui t e cl ear of t he r oad ; and wi t h r espect t o

wat er whi ch ar ose i n spr i ngs at t he si de of t he r oad,

t hi s was pr ovi ded f or by t he si de dr ai ns, whi ch cf l ect u-

al l y cut of l ' al l t hese spr i ngs and di ver t ed t hem al ong

t he r oad si de.

But i n r ever t i ng l o t he st at e of t hi s r oad bef or e t he

exi st ence of t he dr ai ns, we ar e pr esent ed wi t h a wi de

41

cont r ast t o t hat i n whi ch i t was af t er war ds pl aced by

t he j udi ci ous measur es of Mr . Tel f or d. I t was f or mer l y

f ound [ t hat t he nat ur al spr i ngs, whi ch abundant l y

exi st ed i n t he hi gh gr ound on each si de of t he r oad,

di schar ged t hemsel ves i n t he bot t om and si des of t he

excavat i on; and bef or e t he necessar y means wer e t aken

t o pr event t hem r eachi ng t hi s si t uat i on, t he bed of t he

r oad r emai ned const ant l y wet and sat ur at ed wi t h wat er .

Thi s i Sy a case by no means pecul i ar t o t he Hi ghgat e

r oad : I have met wi t h i t i n many ot her s, wher e, as i n

t he] pr esent i nst ance, t he const r uct i on of deep and ca-

paci ous si de dr ai ns, whi ch act ed as channel s t o cut ol F

and di ver t t he wat er f r om ent er i ng t he conf i nes of t he

r oad, pr oved t he onl y ef f ect ual r emedy. We may now

r eadi l y concei ve t he gr and secr et of al l t he pr evi ous

Page 28 of 103

f ai l ur es i n t he var i ous at t empt s made t o i mpr ove t hi s

r oad ;

i t i s per f ect l y evi dent , t hat so l ong as t he cl ayey

bed of t he r oad cont i nued t o be sat ur at ed wi t h wat er ,

i t was capabl e of di spl acement by any wei ght passi ng

over i t ; and t hus no means coul d be i nvent ed t o pr event

i t f r om r i si ng, and mi xi ng wi t h each successi ve body of

mat er i al s l ai d upon t he r oad.

42

CHAPTER V.

On t he Use of Concr et e composed of Gr avel and Li me, as

a Foundat i on f or Roads i n pl aces wher e pi t chi ng

St ones cannot be pr ocur ed.

The descr i pt i ons of st one whi ch mi ght wi t h pr o-

pr i et y be used f or a pi t ched f oundat i on ar e so var i ous,

and ar e so ext ensi vel y f ound t hr oughout Engl and, t hat

i n f ew count i es t he sur veyor s ar e wi t hout t he means of

adopt i ng t hat met hod of secur i ng a har d subst ant i al

j . oad. Never t hel ess, i n t he nei ghbour hood of London,

and i n some ot her di st r i ct s, par t i cul ar l y Nor f ol k, Suf -

f ol k, Cambr i dge, and t he adj oi ni ng count i es, wher e t he

pl ace of t he st r at i f i ed r ocks i s suppl i ed by beds of gr avel ,

i t wi l l be f ound an expensi ve, and i n some cases al most

an i mpr act i cabl e pr oceedi ng, t o pr ocur e and l ay down

st ones, as a pi t cl i ed f oundat i on f or t he r oad mat er i al

t o r est upon. I shoul d by no means r ecommend t he

adopt i on of t hi s ki nd of f oundat i on i n pl aces wher e t he

expense woul d exceed t he pr i ce of concr et e, or say

f r om J3. v. t o Qs. per cubi c yar d ; and shal l t her ef or e now

pr oceed t o poi nt out t he way i n whi ch gr avel i t sel f may

be appl i ed t o t he pur pose of secur i ng as har d and t i r m

a r oad, and one as l i t t l e subj ect t o dest r uct i on, as any

t hat coul d be f or med i n a count r y wher e t he har dest

ki nds of st one ar e wi t hi n t he r each of t he sur veyor .

The concr et e I am about t o descr i be wi l l be di f Fer ent

i n one i mpor t ant par t i cul ar f r om t hat used on t he Hi gh-

gat e Ar chway r oad, al t hough i nt ended t o ef f ect t he same

obj ect , of pr event i ng t he sub- st r at um on whi ch t he r oad

4: 3

i s f or med f r om bei ng di spl aced, and f r om r i si ng up t o

mi x wi t h t he super i or st r at um of r oad mat er i al . I n

some r espect s t he concr et e of l i me, al t hough much

cheaper t han t hat f or med wi t h cement , possesses ad-

vant ages over t he l at t er ; but i f i t shoul d hence be

i nf er r ed, t hat t he expense of t he cement ed bot t om at

Hi ghgat e was on t hi s account unnecessar y and wast e-

f ul , i t must be r emember ed, as some apol ogy, t hat t he

vi r t ues of l i me i n f or mi ng concr et e wer e not t hen so

ext ensi vel y known as t hey have si nce become ; and

had t hi s wor k now t o be per f or med, I have no doubt

t hat t he concr et e of l i me woul d be used i n pr ef er ence

t o cement .

Page 29 of 103

The pr i nci pal di f f er ence bet ween t he t wo ki nds of

concr et e, ar i ses f r om t he l i abi l i t y of cement t o br eak

and cr umbl e when exposed t o pr essur e, t o per cussi on,

or t o any ot her vi ol ent di st ur bi ng f or ce ; and when

once a f r act ur e has t aken pl ace, i t i s a char act er i st i c

of cement t hat t he par t s wi l l never agai n uni t e.

Ther ef or e i t i s t hat cement , al t hough ext r emel y val u-

abl e as a means of f or mi ng a ver y sol i d ar t i f i ci al st one,

by uni t i ng i nt o one mass a body of br oken st one or

pebbl es

and al t hough i t possesses t he r emar kabl e pr o-

per t y of set t i ng i n al l si t uat i ons, even under wat er , i n a

ver y shor t t i me af t er i t s mi xt ur e

i s yet har dl y a saf e

mat er i al t o use i n any pl ace wher e i t i s subj ect t o t he

di st ur bances al r eady ment i oned, by whi ch t he adhesi on

of i t s const i t uent par t s wi l l cer t ai nl y be dest r oyed ; and

t hi s havi ng once t aken pl ace t he whol e bi ndi ng vi r t ue of

t he cement i s gone.

I r egr et t hat I have never had an oppor t uni t y of

seei ng a speci men of t he cement ed bot t om t aken f r om

t he Hi ghgat e Ar chway r oad, af t er i t had been l ai d

down a suf i i ci ent l engt h of t i me t o pr ove i t s dur abi l i t y.

I f such a speci men coul d be pr ocur ed, i t i s not i mpr o-

44

babl e t hat i t woul d be f ound i n a f r act ur ed condi t i on ;

and t hi s woul d of cour se pr ove a ver y st r ong conf i r ma-

t i on of t he not i on wi t h whi ch I am now ver y st r ongl y

i mpr essed, t hat l i me concr et e, f r om t he gr eat er degr ee

of t oughness i t possesses, and t he consequent absence

of t hat br i t t l eness and t endency t o br eak whi ch ar e so

r emar kabl e i n cement , i s act ual l y much t he super i or

mat er i al of t he t wo as a f oundat i on f or r oads.

The use of l i me concr et e, al t hough an i nt r oduct i on

of moder n t i mes, and cer t ai nl y one of r at her a novel

char act er , der i ves i t s r eal or i gi n f r om a ver y r emot e

per i od. We have i ndi sput abl e evi dence t hat t he Ro-

mans i n const r uct i ng t hei r mi l i t ar y ways, par t i cul ar l y

i n Fr ance, adopt ed t he pr act i ce of f or mi ng a concr et e

f oundat i on composed of gr avel and l i me, on whi ch al so

t hey pl aced l ar ge st ones as a pavement . The conse-

quence of a const r uct i on so sol i d has been, t hat i n

many par t s of Eur ope t he or i gi nal bed or cr ust of t he

Roman r oads i s not at t he pr esent day ent i r el y wor n

down, even af t er a l apse of f i f t een cent ur i es.

Wi t h t he vi ew of af f or di ng a modem exampl e i n

whi ch l i me concr et e has been used, I woul d r ef er t o t he

Br i xt on r oad, wher e a concr et e composed of gr avel

and l i me has been r ecent l y appl i ed by Mr . Char l es

Penf ol d, sur veyor t o t he t r ust . I n t hi s case t he pr o-

por t i on of gr avel t o l i me i s t hat of 4 t o 1. The l i me i s

obt ai ned f r om Mer st ham or Dor ki ng, and bef or e bei ng

used i s t hor oughl y gr ound t o powder . The concr et e i s

made on t he sur f ace of t he r oad, and gr eat car e t aken,

when t he wat er i s added, t hat ever y par t i cl e of t he l i me

i s pr oper l y sl aked and sat ur at ed. The bed of concr et e

havi ng been spr ead t o t he dept h of si x i nches over t he

hal f br eadt h of t he r oad, t he sur f ace i s t hen cover ed over

Page 30 of 103

wi t h si x i nches of good har d gr avel or br oken st one,

and t hi s dept h i s l ai d on i n t wo cour ses of t hr ee i nches

45

at a t i me, t he f i r st cour se bei ng f r equent l y l ai d on a

f ew hour s af t er t he concr et e l i as been pl aced i n t he

r oad. The car r i ages however ar e not on any account

al l owed t o pass over i t , unt i l t he concr et e has become

suf f i ci ent l y har d and sol i d t o car r y t he t r af f i c, wi t hout

suf f er i ng t he r oad mat er i al t o si nk and be pr essed i nt o

t he body of concr et e. On t he ot her hand, t he cover i ng

of gr avel i s al ways l ai d on bef or e t he concr et e has be-

come qui t e har d, i n or der t o admi t of a mor e per f ect

bi ndi ng and j unct i on bet ween t he t wo beds, t han woul d

t ake pl ace i f t he concr et e wer e suf f er ed t o become har d

bef or e l ayi ng on t he f i r st cover i ng. The benef i ci al

ef f ect ar i si ng f r om t he pr act i ce of l ayi ng on t he gr avel

exact l y at t he pr oper t i me i s, t hat t he l ower st ones,

pr essed by t hei r own wei ght and by t hose above t hem,

si nk par t i al l y i nt o t he concr et e, and t hus r emai n f i xed

i n a mat r i x, f r om whi ch t hey coul d not easi l y be di s -

l odged. The l ower pebbl es bei ng t hus f i xed, and t hei r

r ol l i ng mot i on consequent l y pr event ed, an i mmedi at e

t endency t o bi nd i s communi cat ed t o t he r est of t he

mat er i al

a f act whi ch must be evi dent , i f we consi der

t hat t he st at e cal l ed bi ndi ng, or r at her t hat pr oduced by

t he bi ndi ng, i s not hi ng mor e t han t he sol i di t y ar i si ng

f r om t he compl et e f i xi ng and wedgi ng of ever y par t of

t he cover i ng, so t hat t he pebbl es no l onger possess t he

power of movi ng about and r ubbi ng agai nst each ot her .

I t i s f ound t hat , i n a ver y f ew days af t er t he f i r st l ayer

has been r un upon, t he ot her or t op cover i ng may be

appl i ed, and shor t l y af t er war ds t he concr et e and t he

whol e body of r oad mat er i al becomes per f ect l y sol i d

f r om t op t o bot t om. The cont r ast t hus pr esent ed t o

t he l engt h of t i me and t r oubl e r equi r ed t o ef f ect t he

bi ndi ng of r oad mat er i al s, wher e t he whol e mass i s l ai d

on l oose, i s al one a ver y st r ong r ecommendat i on i n

f avour of t he concr et e.

46

The exper i ment of usi ng concr et e on t l i e Br i xt on

r oad, al t hough not at pr esent on a ver y ext ensi ve scal e,

has been t r i ed under ci r cumst ances ver y f ar f r om

f avour abl e, and on a par t of t he r oad whi ch had hi t her t o

baf f l ed ever y at t empt t o make i t sol i d. Si nce t he con-

cr et e has been l ai d down, however , t her e i s not a

f i r mer pi ece of r oad i n t he whol e t r ust ; and f r om t he

success of t hi s and ot her t r i al s made by Mr . Penf ol d,

but whi ch I have not seen, I bel i eve i t i s hi s i nt ent i on

t o r ecommend i t i n a gener al and ext ensi ve way t o

sever al t r ust s under whom he act s.

The use of concr et e f or bui l di ng pur poses, wher e

gr eat sol i di t y i s r equi r ed, has now become ver y gener al

and cannot be t oo st r ongl y r ecommended. We have

now exampl es of a ver y ext ensi ve sea- wal l , and of

sever al dock and whar f - wal l s, and even of a chur ch,

Page 31 of 103

bui l t ent i r el y of concr et e. I n some of t hese cases, par -

t i cul ar l y i n t hat of t he sea- wal l at Br i ght on, t he l i me

used f or t he concr et e i s sl i ght l y hydr aul i c, possessi ng

t her ef or e t he pr oper t y of set t i ng under wat er . I n some

r oads wher e t he concr et e i s l ai d upon a damp sub- soi l

t hi s qual i t y wi l l be usef ul ; but i t i s by no means essen-

t i al t o t he f or mat i on of a per f ect concr et e, as any

descr i pt i on of har d st r ong st one l i me wi l l admi r abl y

answer t he pur pose. Fr om t he exper i ence of t he sea-

wal l at Br i ght on, we der i ve t he knowl edge of a f act ,

whi ch may pr ove of some val ue t o t hose who may

have occasi on t o use concr et e i n t he nei ghbour hood of

t he coast , namel y, t hat t he sal t wat er of t he sea makes

excel l ent mor t ar , and t he pebbl es of t ho sea shor e f or m

excel l ent mat er i al f or mi xi ng wi t h t he l i me t o make

concr et e. Ther e i s, t her ef or e, good r eason l or sup-

posi ng t he pr ej udi ce t o be gr oundl ess, whi ch i s ent er -

t ai ned by many engi neer s and ar chi t ect s, agai nst t he

empl oyment of any mat er i al cont ai ni ng sal i ne par t i cl es,

i n maki ng ei t her mor t ar or concr et e.

47

I shoul d her e ment i on, t hat whi l e t he i mpr ovement

descr i bed i n t he pr ecedi ng chapt er was i n pr ogr ess on

t he Hi ghgat e Ar chway r oad, one par t i cul ar spot of t he

r oad about f our f eet squar e, near t he Wel l i ngt on I nn,

bei ng f ound ext r emel y sof t and el ast i c, T t r i ed her e on

my own r esponsi bi l i t y a concr et e composed of gr avel

and bl ue l i as st one l i me, whi ch was subst i t ut ed f or t he

cement concr et e, and t he r esul t of t hi s cer t ai nl y was t o

r ender t hat par t of t he r oad as per f ect as al l t he r est .

I n consequence of t hi s t r i al , st r engt hened by a ver y

st r ong not i on of my own t hat l i me concr et e woul d be

f ound at l east equal l y et f ect i ve wi t h t hat of cement , I

consul t ed Mr . Rhodes, ci vi l engi neer , on t he subj ect ,

as he had al ways t aken gr eat i nt er est i n t he i mpr ove-

ment of t hi s r oad ; and hi s opi ni on det er mi ned me t o

r equest per mi ssi on f r om Mr . Tel f or d t o l ay down a

smal l quant i t y of t he l i as l i me concr et e on anot her

par t of t he wor k. Mr . Tel f or d havi ng af t er war ds agr eed

t o t hi s at t he f ur t her suggest i on of Mr . Rhodes and Mr .

M' Nei l , i t was accor di ngl y t r i ed on a shor t l engt h of t he

r oad near t he summi t of t he hi l l . The t r i al , I shoul d

st at e, was not made unt i l af t er I had f i ni shed my con-

t r act f or t he wor k ; and I r egr et t o say, t hat t he t i me

chosen was ver y i nj udi ci ous, and no pr ecaut i ons t o

pr ot ect i t f r om t he weat her bei ng t aken, t he f r ost com-

pl et el y dest r oyed t he l i me, and t he concr et e was never

al l owed pr oper l y t o set . I n consequence of t hi s f ai l ur e,

i t was r epor t ed t hat t he l i me concr et e coul d not be

used as a subst i t ut e f or t he cement ed bot t om; and not -

wi t hst andi ng t he compl et el y successf ul and ver y sat i s -

f act or y t r i al I had mysel f made at t he Wel l i ngt on I nn,

t he i dea of usi ng l i me concr et e was abandoned. I t wi l l

onl y be f ai r t owar ds Mr . M' Nei l , however , t o acqui t

hi m ent i r el y of al l bl ame f or t he f ai l ur e of t he t r i al made

af t er I had l ef t t he wor k. I bel i eve i t was hi s i nt ent i on

Page 32 of 103

48

f ai r l y t o have t r i ed t he l i me concr et e ; but f r om some

cause or ot her wi t h whi ch I am not acquai nt ed, he was

pr event ed f r om at t endi ng t o i t hi msel f ; and t he per son

he ent r ust ed havi ng negl ect ed i t , I do not t hi nk Mr .

M' Nei l ever knew t he cause of t he f ai l ur e.

Wi t hout however dr awi ng any i nf er ence as t o t he

val ue of l i me concr et e, f r om t he t r i al s made on t he

Hi ghgat e r oad, I am deci dedl y of opi ni on t hat t hi s

mat er i al , i f gener al l y adopt ed as a f oundat i on f or r oads,

wi l l ef f ect one of t he gr eat est i mpr ovement s t hat has

f or many year s been pr esent ed t o t he not i ce of t he

publ i c. I n t he nei ghbour hood of t he met r opol i s par t i -

cul ar l y, wher e dur abl e mat er i al s ar e so exceedi ngl y

expensi ve, and wher e t he Thames gr avel can be had at

such a cheap r at e, t he expense of const r uct i ng t he best

descr i pt i on of r oad wi l l be ver y much di mi ni shed. The

Thames gr avel can be del i ver ed, at a di st ance of f r om

t wo t o t hr ee mi l es f r om t he r i ver , at about 3. s. per cubi c

yar d; har d f l i nt s and wel l pr epar ed pi t gr avel at about

6s. or 6s. 6d. per yar d; Guer nsey gr ani t e, Mount sor r el ,

Dar t moor , Hay t or , or Scot ch gr ani t e, f r om 15s. t o 20s.

per cube yar d. I am cl ear l y of opi ni on, t hat t he f i r st of

t hese mat er i al s

t he r i ver gr avel

ought never t o be

used as an upper cover i ng or sur f ace f or any r oad of

much t r af f i c, even i f i t coul d be had f or not hi ng. Fr om

i t s ext r emel y br i t t l e nat ur e, i t not onl y cr umbl es and

br eaks t o pi eces i mmedi at el y when pr essur e comes

upon i t , but i t act ual l y i s decomposed, and cr umbl es

i nt o sand and gr i t when act ed upon by t he al t er nat i ons

of t he weat her al one. On accoi mt al so of i t s r ound and

smoot h sur f aces, whi ch ar e per f ect l y di vest ed of al l

mat er i al of an adhesi ve nat ur e, t he bi ndi ng of t hi s

gr avel i s ent i r el y out of t he quest i on unt i l i t be made

angul ar ; and t hi s never happens except when t he whol e

i s gr ound i nt o such smal l par t i cl es as t o r ender i t qui t e

49

unf i t f or a car r i age r oad. The consequence i s, t hat t hi s

gr avel no sooner begi ns t o bi nd or set , t han t he f i r st r ai n

or t haw, af t er ever so sl i ght a f r ost , r ender s i t qui t e i m-

passabl e ; and hence i t i s, t hat wher e t hi s mat er i al i s

much used on t he met r opol i t an r oads, t he publ i c can

never have t he advant ages of a sol i d, har d, and f i r m

sur f ace f or any l engt h of t i me. Even i n t he ver y best

summer weat her such a r oad cannot st and many days;

t he publ i c ar e t her ef or e const ant l y annoyed, ei t her wi t h

a new cover i ng, whi ch occasi ons an i mmense f r i ct i on

and gr eat wear and t ear of hor ses and gear of ever y

descr i pt i on, or t hey have t o t r avel on a r oad whi ch i s

so sof t t hat t he wheel s of car r i ages si nk i nt o i t wi t h

per f ect f aci l i t y

i n ei t her case t he f r i ct i on, and conse-

quent dest r uct i on of hor ses, car r i ages, and har ness, and

t he annoyance t o t hose who t r avel on i t , must be exces -

si ve. When we t ake f ur t her i nt o consi der at i on t he

number of men who must be i n const ant at t endance t o

r ake i n t he r ut s, and t o cl ear t he r oad of t he usel ess

mat er i al s when gr ound t o pi eces, and al so t he const ant

expense of l ayi ng on new mat er i al s, I t hi nk f ew wi l l

Page 33 of 103

be i ncl i ned t o di sput e wi t h me t he i mpol i cy of usi ng

r i ver gr avel as an upper cover i ng on t he met r opol i t an

r oads. Si nce, t hen, i t cannot be pr of i t abl y or j udi -

ci ousl y used as an upper cover i ng, i t woul d be obvi -

ousl y i mpr oper t o appl y i t as a bed on whi ch t o pl ace

t he har der st one, whi ch f or ms t he r oad mat er i al . Thi s

must be evi dent , f r om t he, wel l known f act , t hat t he

bi ndi ng and set t i ng of any r oad cover i ng, however deep,

al ways commences at t he bot t om of t he mat er i al ; and

i t wi l l occur t o ever y one who consi der s t he subj ect ,

t hat no bi ndi ng of a st r onger and heavi er mat er i al can

t ake pl ace on anot her of a sof t er or l i ght er descr i pt i on

t han i t sel f ; because t he upper mat er i al , bei ng t he

har der and st r onger of t he t wo, wi l l si nk down and

E

50

pr ess t he ot her asi de i nst ead of uni t i ng wi t h and bi ndi ng

i nt o i t . I n t hi s way t he sof t er mat er i al woul d evi dent l y

ver y soon be dest r oyed; because, unt i l t he bi ndi ng of a

r oad cover i ng t akes pl ace, t he f r i ct i on and r ubbi ng of

t he st ones amongst t hemsel ves i s ver y consi der abl e and

ver y dest r uct i ve. The ef f ect of t hi s may r eadi l y be

concei ved i n t he case of a sof t br i t t l e mat er i al l i ke t he

r i ver gr avel , mi xed up as i t soon woul d be wi t h a har d

si l i ci ous gr ani t e or whi nst one. Exper i ence i n f act has

shown, i n a gr eat number of cases, t hat i t i s qui t e i m-

possi bl e t o pr oduce ef f ect ual bi ndi ng unl ess t he bot t om

be sol i d, and t o a cer t ai n ext ent unyi el di ng ; and hence,

i f t wo or mor e var i et i es of mat er i al s ar e t o be used i n

t he cover i ng, t he har dest must be pl aced i n t he bot t om

and not on t he t op.

Fr om t hese consi der at i ons i t woul d evi dent l y be a

most i mpor t ant obj ect , i f an i nf er i or and ot her wi se

wor t hl ess mat er i al , such as r i ver gr avel , coul d be so

appl i ed i n r oadmaki ng as t o f or m a har d unyi el di ng

body, on whi ch a cover i ng of har d st one mi ght be l ai d,

wi t hout pr oduci ng t he same ef f ect s as i f l ai d on a l oose

bed of t he gr avel . I t i s on t hi s gr ound t hat I beg t o

r ecommend t he use of concr et e, composed of l i me and

r i ver gr avel , whi ch bei ng ent i r el y di vest ed of ear t hy

mat t er , i s pr obabl y one of t he best mat er i al s t hat can

be f ound f or f or mi ng a st r ong and dur abl e concr et e.

Thi s ki nd of gr avel has been used f or t he concr et e

pl aced i n t he f oundat i ons of many i mpor t ant bui l di ngs ;

amongst whi ch I may ment i on par t i cul ar l y, t he Peni -

t ent i ar y at Mi l l bank, wher e a concr et e f oundat i on was

l ai d by my f at her , t he l at e Mr . John Hughes. Fr om a

l ong exper i ence of t he val ue of concr et e, i n t hi s and

ot her si t uat i ons, I am per suaded t hat t hi s mat er i al wi l l

f or m one of t he best f oundat i ons f or a r oad t hat has

ever been t r i ed. The nat ur e of t he l i me, whi ch com-

51

poses so pr i nci pal an i ngr edi ent i n t hi s concr et e, r en-

der i ng i t qui t e i mper vi ous t o wat er , no spr i ngs can

Page 34 of 103

br eak up t hr ough i t , and t hi s i n damp si t uat i ons i s an

ext r emel y usef ul pr oper t y. I have al r eady al l uded t o

t he t oughness of l i me concr et e ; and I t hi nk I may add,

t hat when t hi s mat er i al has once become wel l set i t s

har dness can scar cel y be exceeded

i t t hen becomes i n

f act per f ect st one. As an i nst ance i n cor r obor at i on of

t hi s, I woul d ment i on, t hat bef or e Mr . Tel f or d det er -

mi ned on usi ng concr et e so ext ensi vel y, i n t he f oun-

dat i ons under some of t hose heavy br east - wal l s and

war ehouses at t he St . Kat her i ne' s Docks, a speci men

of t he concr et e, whi ch I have al r eady st at ed was some

year s bef or e pl aced under t he Peni t ent i ar y, was by

aut hor i t y al l owed t o be dug out . I saw a par t of t hi s

speci men, and I never i n my l i f e wi t nessed any mat er i al

r esembl i ng so near l y t he Puddi ng- st one r ock

a con-

gl omer at e Avhi ch i s al ways consi der ed an exceedi ngl y

har d and per f ect st one.

I shoul d r ecommend f or al l t he pr i nci pal r oads near

London

af t er al l t he suppl i es of wat er f r om t he si des

as wel l as t hat f al l i ng on t he r oad have been pr oper l y

i nt er cept ed by l ongi t udi nal si de dr ai ns and t r ansver se

ones l eadi ng i nt o t hem, and occur r i ng as of t en as t he

nat ur e of t he sub- soi l may r equi r e

t hat a bed of l i me

concr et e si x i nches i n t hi ckness, mi xed as al r eady

descr i bed, be l ai d al l over t he br eadt h of t he r oad ; and

t hat t hi s bed be af t er war ds cover ed wi t h si x i nches of

t he best f l i nt or pi t gr avel t hat can be pr ocur ed, i n t wo

cour ses of t hr ee i nches at a t i me ; or wi t h, what i n my

opi ni on woul d be a much mor e l ast i ng and ser vi ceabl e

mat er i al , f our i nches of br oken gr ani t e st one : and I am

convi nced t hat a r oad so const r uct ed, however bad t he

under st r at um may be, wi l l pr ove one of t he har dest ,

E 2

52

most dur abl e, and at t he same t i me one of t he cheapest

r oads ever f or med i n t he nei ghbour hood of London.

I woul d her e however suggest , t hat t he sur veyor ( or

whoever may have char ge of a r oad so const r uct ed)

ought never t o admi t of t he cover i ng bei ng wor n down,

so as t o per mi t t he concr et e t o be act ed upon or i n any

manner di st ur bed ; but as soon as t he upper sur f ace i s

wor n down t o wi t hi n t wo i nches, or at most t o wi t hi n

one i nch of t he concr et e, a new cover i ng t he same t hi ck -

ness as bef or e shoul d be i mmedi at el y l ai d on.

I t may not be consi der ed ver y f or ei gn t o t hi s subj ect

t o r emar k, t hat i n gent l emen' s par ks, gar dens, and pl ea-

sur e- gr ounds, i t i s exceedi ngl y di f f i cul t , i f not i mpr ac -

t i cabl e, t o make or nament al car r i age r oads or pr i vat e

wal ks by t he ol d syst em of l ayi ng on l oose gr avel or

br oken st ones; f or what ever pai ns be t aken i n sel ect i ng

t he best ki nd of gr avel and af t er war ds i n f or mi ng and

r ol l i ng, wor ms wi l l f i nd t hei r way t hr ough aj i d dest r oy

i t by deposi t i ng a por t i on of adhesi ve ear t h wher ever

t hey wor k t o t he sur f ace ; and t hese deposi t s ar e so

numer ous, par t i cul ar l y i n t he aut umn and t hr ough t he

wi nt er and spr i ng of t he year , t hat ' i n t he case of t he

Page 35 of 103

car r i age- r oads, t hi s ear t hy mat er i al f i r st adher es t o t he

r i ms of t he wheel s, and t hen agai n st i cki ng t o t he gr avel ,

t ear s up t he whol e sur f ace t o t he ent i r e dest r uct i on of

t he r oad. Gar den wal ks f r om t hi s cause f r equent l y

cannot be t r aver sed wi t h any pl easur e

t he di r t adher es

t o t he f eet and i s so exceedi ngl y unpl easant , t hat such

r oads and wal ks, i nst ead of havi ng a har d, cl ean, and

smoot h sur f ace, become di r t y and unsi ght l y i n t he ex -

t r eme. I woul d r ecommend i n such pl aces, t hat t he

r oads and pat hs shoul d uni f or ml y he made wi t h a con-

cr et e bot t om of onl y a ver y f ew i nches i n t hi ckness; say

t hr ee i nches f or car r i age r oads and t wo i nches f or pat hs,

53

and wi t h a sl i ght cover i ng of bi ndi ng gr avel on t he t op.

Thi s syst em, I t hi nk, woul d ef f ect ual l y pr event t he r oads

f r om bei ng dest r oyed i n t he manner I have descr i bed ;

f or i ndependent of t he ant i pat hy whi ch t he wor m, and I

may add ever y descr i pt i on of i nsect , ent er t ai ns agai nst

l i me, and not wi t hst andi ng t hei r capabi l i t i es of bor i ng,

t hey never coul d penet r at e hal f an i nch i nt o t he con-

cr et e. As an i nst ance of t he per sever ance of wor ms,

and of t he mi schi ef s t hey somet i mes occasi on, T have

mysel f , dur i ng a ver y dr y hot summer , met wi t h t hem i n

canal excavat i ons, f our f eet bel ow t he sur f ace i n har d

cl ay ; and I have known t hem penet r at e af t er war ds out

of t hi s dept h and t hr ough t hr ee f eet of cl ay puddl e,

t her eby act ual l y occasi oni ng l eakage i n t he canal .

54

CHAPTER VI .

On t he Dr ai nage of Roads.

Of al l t he consi der at i ons whi ch cl ai m t he at t ent i on

of t he pr act i cal r oadmaker , t hat of compl et e and ef f ec -

t i ve dr ai nage i s t he most i mpor t ant , and gener al l y t he

f i r st whi ch shoul d be at t ended t o. Al t hough some

r oads ar e f ar mor e f avour abl y si t uat ed t han ot her s wi t h

r espect t o t he ext ent of ar t i f i ci al dr ai nage r equi r ed, i t

i s qui t e cer t ai n t hat no r oad has any chance of becomi ng

per f ect unl ess t he under st r at um be r ender ed per f ect l y

dr y, ei t her by nat ur al or ar t i f i ci al means. The ver y

best mat er i al s ever empl oyed t o f or m t he cr ust of a r oad

wi l l be ent i r el y t hr own away, unl ess t hi s ver y essent i al

par t of t he wor k be f i r st per f or med ; and on t he ot her

hand, many ver y excel l ent r oads owe t hei r super i or i t y

al most ent i r el y t o t he benef i ci al ef f ect s of good dr ai nage.

I n t he f or mat i on of a new r oad, or i n i mpr ovi ng t hose

al r eady made, no money i s so wel l l ai d out as t hat ex -

pended i n pr ocur i ng per f ect dr ai nage ; and what may at

f i r st si ght appear t o be an unnecessar y out l ay, wi l l i n

t he end be f ound t he most economi cal appl i cat i on of

capi t al t hat can be devi sed.

The par t i cul ar ki nd of dr ai nage r equi r ed f or r oads

Page 36 of 103

must of cour se be det er mi ned by l ocal and ot her

ci r cumst ances; and i t may now be advi sabl e t o con-

si der some of t he var i et i es of dr ai nage t o whi ch t hese

wi l l gi ve r i se.

When a r oad i s f or med on a l evel wi t h t he gr ound

on each si de, t her e wi l l sel dom be f ound much di f f i -

55

cul t y i n pr event i ng t he accumul at i on of wat er . I n t hi s

case t he r oad wi l l not of cour se i nt er sect any nat ur al

spr i ngs, whi ch ar e of t en f ound exceedi ngl y t r oubl esome

i n ot her si t uat i ons, and t he onl y wat er t o be car r i ed of f

by t he dr ai ns, i s t hat f al l i ng on t he sur f ace of t he r oad

i n t he f or m of r ai n and snow. The most f avour abl e

ci r cumst ances under whi ch a r oad can be pl aced f or

ef f ect i ng t hi s, ar e t hose i n whi ch a l ongi t udi nal i ncl i na-

t i on of not l ess t han si x or ei ght f eet i n a mi l e exi st s

i n t he di r ect i on of t he r oad. Thi s f al l of 1 i n 880 or 1

i n 660, al t hough so near l y hor i zont al as t o be scar cel y

per cept i bl e, wi l l be suf f i ci ent t o car r y of f t he wat er ; but

i t i s advi sabl e i f possi bl e t o obt ai n a gr eat er f al l , whi ch

wi l l add ver y l i t t l e t o t he dr aught of t he r oad. I n no

case however shoul d t he f al l of t he r oad be l ess t han

si x f eet i n a mi l e ; and wher e a gr eat er cannot be ob-

t ai ned t he ut most at t ent i on must be pai d t o t he st at e of

t he si de dr ai ns, f or unl ess t hese be kept wel l cl eaned

out , and unobst r uct ed by weeds or ot her mat t er s, i t i s

obvi ous t hat t he wat er wi l l not pass of f . I f t he bed of

t he r oad be f or med wi t h a r egul ar convexi t y, as de-

scr i bed i n t he second chapt er , t her e wi l l be no necessi t y

f or a cent r e l ongi t udi nal dr ai n ; nor af t er t he r oad has be-

come har dened wi l l t r ansver se mi t r e dr ai ns be r equi r ed,

because t he wat er whi ch may soak t hr ough t he upper

cover i ng wi l l nat ur al l y r un of f t o t he si de dr ai ns. Shoul d

t he wat er be f ound t o st agnat e i n pool s over any par t

of t he si de dr ai ns, t he l abour er i n char ge of t he r oad

shoul d, as soon as he di scover s t hi s, dr i ve t he poi nt of hi s

pi ckaxe t hr ough t he upper cover i ng down t o t he r ubbl e

st ones wi t h whi ch t he dr ai ns ar e f i l l ed, when t he wat er

wi l l f i nd i t s way of f t he sur f ace and make a r eady

escape by means of t he si de dr ai n. As t he f i el d dr ai ns

shoul d al ways be l ower t han t he si de dr ai ns, and gene-

r al l y wi l l be t he l owest dr ai nage t hat can be had f or t h- ^

56

r oad, i t wi l l be necessar y, par t i cul ar l y wher e t he l ongi -

t udi nal f al l of t he r oad i s not consi der abl e, t o make

f r equent communi cat i ons bet ween t he si de dr ai ns and

t he out er f i el d dr ai ns. These communi cat i ons may be

made at i nt er val s of about f or t y or f i f t y yar ds, and may

ei t her consi st of ear t hen pi pes l ai d acr oss under t he

mound and under t he f oot pat h or ver ge, or of br i ck

dr ai ns, havi ng an ar ea or openi ng of about ei ght een

squar e i nches. The f i el d dr ai ns, pl aced on t he out si de

of t he mound or qui ckset bank, wi l l of cour se be open

dr ai ns, and wi l l ser ve t o dr ai n t he adj acent l ands as

wel l as t he r oad i t sel f . The si de dr ai ns, however ,

Page 37 of 103

f or med wi t hi n t he l i mi t s of t he r oad, shoul d be f i l l ed

wi t h cl ean car ef ul l y sel ect ed r ubbl e st ones, not l ess i n

si ze t han a cube of t hr ee i nches nor l ar ger t han a cube

of f i ve i nches, t hat i s, cont ai ni ng f r om about t hi r t y t o

one hundr ed cubi cal i nches. These dr ai ns have some-

t i mes a f i at and sough t i l e pl aced i n t he bot t om bef or e

t he r ubbl e st ones ar e f i l l ed i n. I shoul d however r e-

commend t he f ol l owi ng const r uct i on, namel y, a f l at t i l e

i n t he bot t om, t he si des t o be br i cks on edge pl aced on

t he f l at t i l e, and t he t op a t i l e si mi l ar t o t hat i n t he

bot t om. I pr ef er br i cks f or t he si des of t he dr ai n, be-

cause t he sough t i l es ar e so l i abl e t o br eakage, an

obj ect i on whi ch does not appl y t o t he f l at t i l es. These

l at t er ought t o be used f or t he bot t om and t op of t he

dr ai n, because t hey occupy l ess space t han br i cks, and

consequent l y l eave mor e r oom f or t he r ubbl e st ones.

The br i cks may be pl aced on t he bot t om t i l e about f our

i nches apar t , so as t o make t he openi ng of t he dr ai n

about ei ght een squar e i nches; and i t wi l l be advi sabl e

t o l eave a space of about a quar t er of an i nch at t he

end of each cover i ng t i l e, t o al l ow t he wat er per col at i ng

t hr ough t he r ubbl e st ones mor e f r eel y t o ent er t he br i ck

dr ai n. The si de dr ai ns shoul d al ways be f or med at

57

l east a f oot bel ow t he bed of t he r oadway, and t hey

shoul d never be made wi t hout ei t her t he sough and t i l e,

or t he br i ck dr ai n above descr i bed; because, i n addi t i on

t o t he f aci l i t y t hus gi ven t o t he f l owi ng of t he wat er , t he

br i cks and t i l es pr event t he r ubbl e st ones f r om bei ng

pr essed, and si nki ng i nt o t he gr ound, as t hey woul d

ot her wi se be l i kel y t o do.

Not wi t hst andi ng, however , al l t he pr ecaut i ons t hat

can be t aken, i t wi l l somet i mes be f ound t hat t he ver y

best const r uct ed dr ai ns become choked up and pr event

t he wat er f r om escapi ng. I n such a case, t he occur r ence

of whi ch wi l l soon be evi dent f r om t he appear ance of

wat er on t he sur f ace i mmedi at el y on t he t op of t he

dr ai n, and somet i mes on t he r oad i t sel f , t he wor kmen

shoul d i mmedi at el y pr oceed t o open t he suspect ed

dr ai n, a l i t t l e l ower down t han wher e t he wat er i s ob-

ser ved t o st op or br eak out upon t he r oad. The dr ai n

wi l l now appear dr y at t hi s poi nt , demonst r at i ng t hat

t he f l ow of wat er i s her e i nt er r upt ed, but t he dr ai nage

bel ow i s per f ect . The st ones and t i l es must t hen be

r egul ar l y cl eaned out , and when r epl aced t he dr ai n wi l l

act as wel l as ever . Al t hough a st oppage i n one of t he

si de dr ai ns, i f al l owed t o cont i nue, woul d soon dest r oy

a good r oad, and par t i cul ar l y i f i t happen i n wet

weat her , yet not hi ng i s easi er when once di scover ed

t han t o ef i ect t he cur e as above descr i bed.

The next case of dr ai nage t o be consi der ed i s, wher e

t he r oad has t o be excavat ed bel ow t he nat ur al gr ound

sur f ace, a si t uat i on i n whi ch t he di f f i cul t i es ar i si ng f r om

t he pr esence of wat er , and t he necessi t y of pr event i ng

i t f r om di st ur bi ng t he bed of t he r oad, ar e f ar mor e nu-

mer ous t han wher e t he r oad i s f or med on a l evel wi t h

t he nat ur al sur f ace. Al most ever y st r at i f i cat i on wi t h

whi ch we ar e acquai nt ed, except cl ay and some of t he

Page 38 of 103

ver y har d r ocks, ar e capabl e of bei ng penet r at ed by

58

wat er , whi ch per col at es t hr ough t hem unt i l i t ar r i ves at

some l ow l evel wher e i t can be di schar ged. I t i s i m-

possi bl e, however , f r om mer el y knowi ng t he nat ur e of a

st r at um t o be cut t hr ough, t o pr edi ct wi t h anyt hi ng l i ke

cer t ai nt y whet her i t wi l l be f ound t o cont ai n wat er .

Thi s depends so much upon i t s posi t i on wi t h r espect t o

ot her st r at a, t hat i t i s onl y upon a vi ew of t he si t uat i on,

and an accur at e knowl edge of al l t he ci r cumst ances,

t hat a cor r ect j udgment can be ar r i ved at . For i n-

4 st ance, a bed of sand

B^ . ^ , ^ - - ^ 7j ; ^ ^ ; f r m: ^ or gr avel , i n t he po-

Cl ay. si t i on shown i n t he

annexed sket ch, wi l l

pr obabl y r ecei ve t he wat er f al l i ng on t he cr own of t he

hi l l , whi ch wi l l t hen pass t hr ough i t f r om A t o B.

wher e i t may di schar ge i nt o t he val l ey. But i f t he bed

of sand or gr avel be f ound i n t he shape of a basi n, as

i n Ji g. 2, i t i s obvi ous

t hat al l t he Wat er i n

^ t he sand cannot pass

Cl at / . of f , because i t s f l ow i s

i mpeded by t he under l yi ng bed of cl ay. The hor i -

zont al l i ne A B, wi l l r epr esent t he l owest l evel of

dr ai nage, and bel ow t hi s l evel we may expect t o f i nd

t he st r at i f i cat i on f ul l of wat er .

Al t hough t he r el at i ve posi t i ons of di f f er ent st r at a

ar e exceedi ngl y var i abl e, i t wi l l gener al l y be f ound t hat

any par t i cul ar bed of por ous gr avel , sand, or chal k i s

wet or dr y, accor di ng as t he wat er whi ch soaks i nt o i t

i n one pl ace, i s or i s not dammed up by some st r at um

i mper vi ous t o wat er , of whi ch nat ur e i s al most ever y

var i et y of cl ay. The deep excavat i ons made f or t he

canal s, and mor e r ecent l y f or some r ai l ways, af l br d

r emar kabl e i nst ances of t he t r ut h and pr opr i et y of t hi s

di st i nct i on. For i nst ance, t he bor i ngs made on t he l i ne

69

of t he Br i ght on Rai l way, i n t he nei ghbour hood of Mer st -

ham and Oxt ead, as wel l as t he quar r i es whi ch ar e

ext ensi vel y wor ked at var i ous pl aces al ong t he Sur r ey

chal k r ange, showed t he chal k t o be al most qui t e dr y ;

wher eas on t he London and Bi r mi ngham Rai l way,

i n t he nei ghbour hood of Tr i ng, t he chal k i s ent i r el y

sat ur at ed wi t h wat er , and al t hough bel ongi ng t o t he

same f or mat i on as t he Sur r ey chal k, i s ext r emel y di f -

f er ent i n appear ance and t ext ur e, bei ng gener al l y of a

di ngy cr eam col our , and ver y much shat t er ed f or a con-

si der abl e dept h. The r eason of t he di f f er ence i s si mpl y

t hi s, t hat i n Sur r ey t he gaul t br i ck ear t h, a st r ong

Page 39 of 103

t enaci ous cl ay whi ch under l i es t he chal k i n bot h cases

at i t s out cr op, r i ses ver y l i t t l e above t he l evel of t he

l ower chal k beds, and t her ef or e t he wat er per col at i ng

t hr ough t he chal k i s al l owed t o escape over t he cl ay,

whi ch i t accor di ngl y does, f or mi ng sever al smal l st r eams

f l owi ng sout hwar d. But at Tr i ng t he gaul t r i ses t o a

consi der abl e hei ght above t he l evel of t he l ower chal k

beds, t her eby dammi ng back t he wat er whi ch r emai ns

i n t he chal k, at l east as hi gh as t he l evel of a hor i zont al

l i ne dr awn f r om t he j unct i on of t he gaul t and chal k

st r at a. Hence i t i s easy t o account f or t he compl et e

sat ur at i on of t he chal k i n t hi s par t of t he count r y ; and

on t he same gr ounds, we per cei ve t he or i gi n of t he vast

st r eam of wat er whi ch was f ound t o i ssue f r om t he chal k

excavat i on at Tr i ng, as soon as t he cut t i ng was car r i ed

t hr ough t he bed of gaul t , and t he wat er t hus pr ovi ded

wi t h a channel of escape f r om t he chal k.

I n cut t i ng t hr ough any por ous st r at i f i cat i on, wher e

t he wat er has been hel d back as at Tr i ng, by an under -

l yi ng bed whi ch has al so t o be cut t hr ough, i t i s obvi ous

t hat t he excavat i on i t sel f wi l l ser ve t o dr ai n t he por ous

st r at um as l ow as t he l evel of t he r oad ; and i t wi l l ,

t her ef or e, onl y be necessar y t o make si de dr ai ns of

GO

r at her l ar ger di mensi ons t han i n or di nar y cases; and i t

wi l l somet i mes be f ound a ver y excel l ent and necessar y

expedi ent t o l ay down, al ong t he cent r e of t he cut t i ng,

a cul ver t or bar r el dr ai n of br i ck, i nt o whi ch communi -

cat i ons shoul d be made f r om t he si de dr ai ns, at i nt er -

val s of t went y or t hi r t y yar ds. The openi ng whi ch

t he bar r el dr ai n shoul d have wi l l depend upon t he

quant i t y of wat er ; but ei ght een i nches or t wo f eet

wi l l be f ound suf f i ci ent i n most cases ; and t he bot t om

of t he bar r el dr ai n shoul d al ways be sunk at l east

a f oot l ower t han t he bot t om of t he si de dr ai ns, i n

or der t hat t he wat er f r om t hese may f l ow r eadi l y i nt o

t he cent r e dr ai n.

But per haps t he most di f f i cul t ki nd of excavat i ons

t o dr ai n, ar e t hose whi ch so f r equent l y occur t hr ough a

st r at i f i cat i on of cl ay al t er nat i ng wi t h beds of sand or

gr avel . A r oad cut t o t he dept h of t went y or t hi r t y f eet

may i nt er sect a gr eat number of t hese beds, f r om whi ch

t he wat er wi l l i ssue on t he sl opes, and i f not pr oper l y

guar ded agai nst , wi l l pr oduce t he most i nj ur i ous con-

sequences. Thi s i s pr eci sel y t he case wi t h Hi ghgat e

hi l l , par t i cul ar l y on t he sout h si de of t he Ar chway :

t he wat er cont ai ned i n t he por ous st r at a br eaks out al l

over t he sl opes, car r yi ng down por t i ons of t he l oose

r unni ng sand or gr avel , and t hus under mi ni ng l ar ge

masses of ear t h, whi ch consequent l y sl i p down i nt o

t he r oad. Var i ous expedi ent s have been r esor t ed t o

f or t he pur pose of pr eser vi ng t he sl opes, pr event i ng

sl i ps, and pr ot ect i ng t he r oad f r om t he wat er br eaki ng

out on t he sl opes. At Hi ghgat e, and ot her pl aces,

wel l s or shaf t s, about f our f eet i n di amet er , have been

sunk at sever al par t s of t he sl opes, i nt o whi ch t he

wat er i s al l owed t o dr ai n, unt i l i t meet s at t he bot t om

wi t h some por ous bed of sand or l oose gr avel l ower

Page 40 of 103

t han t he r oad, ( hr ough whi ch i t can pass ol f away f r om

61

t he r oad and t he sl opes. Thi s met hod, al t hough ver y

expensi ve, has sel dom been f ound a ver y ef l ect ual

r emedy. I n my opi ni on, a much bet t er pl an woul d be

t o f or m r ubbl e dr ai ns al ong t he f ace of t he sl opes, i n

or der t o i nt er cept , i f possi bl e, al l t he wat er whi ch

br eaks out , and conduct i t i nt o t he si de dr ai ns at t he

f oot of t he sl opes. No gener al r ul e can be l ai d down

f or t he di r ect i on and i ncl i nat i on whi ch shoul d be gi ven

t o t hese dr ai ns ; but t hey shoul d be so pr oj ect ed as t o

i nt er sect as many of t he spr i ngs as possi bl e, at t he

same t i me t hat a suf f i ci ent f al l must be gi ven t o al l ow

t he wat er t o pass f r eel y al ong t hem. I have mysel f

ver y commonl y adopt ed t hi s pl an i n canal and r oad

excavat i ons, par t i cul ar l y on t he Uni on Canal , i n Scot -

l and, and at For t y- mi l e hi l l , on t he London and Hol y-

head r oad, aud have al ways f ound i t succeed ad-

mi r abl y. The dr ai ns shoul d be f i l l ed wi t h t he same

ki nd of r ubbl e st ones as al r eady descr i bed f or t he r oad-

si de dr ai ns, and t hen cover ed wi t h a t hi n l ayer of

br ushwood, over whi ch ear t h or moul d may be spr ead,

so t hat no ext er nal appear ance of dr ai nage wi l l be

vi si bl e ; and i n al most al l si t uat i ons wher e wat er i s

f ound t o br eak out on t he sur f ace of t he sl opes, t hi s

met hod of dr ai nage wi l l pr ove r emar kabl y ef f ect i ve.

I n al l excavat i ons I shoul d make t he dr ai ns at t he

f oot of t he sl opes of gr eat er dept h and ar ea t han t he

si de dr ai ns f or a sur f ace r oad; and i t wi l l al so be

necessar y t o f or m cat chwat er dr ai ns at t he t op of t he

sl opes, t o i nt er cept t he sur f ace wat er , whi ch woul d

ot her wi se r un down t he sl opes. The f or m and di men-

si ons of t hese dr ai ns must i n some degr ee depend upon

t he nat ur e of t he gr ound i n whi ch t hey ar e made. A

wi dt h of t hr ee f eet at t op, and one f oot si x i nches at

bot t om, and dept h of t wo f eet , wi l l i n most cases be

f ound suf t i ci ent .

62

I t woul d obvi ousl y be i mpossi bl e, wi t hi n any r eason-

abl e l i mi t s, t o gi ve r ul es f or al l cases wher e wat er i s

met wi t h i n r oad excavat i ons; but I have no hesi t at i on

i n asser t i ng ( as t he r esul t of a l ong cour se of pr act i cal

and const ant exper i ence i n mat t er s of t hi s ki nd, ) t hat

t her e i s no case of dr ai nage so di f f i cul t t hat some

means cannot be f ound compl et el y t o over come any

obst acl es t hat may ar i se ; and r ar el y i ndeed i s a t r act

of l and so unsound, t hat i t cannot by j udi ci ous manage-

ment be r ender ed suf f i ci ent l y sol i d and f i r m t o bear t he

wei ght of any r oad whi ch has t o be made t hr ough i t .

I nst ances f r equent l y occur i n whi ch t he adopt i on

of some ver y si mpl e expedi ent wi l l ef f " ect ual l y cause

t he wat er t o di sappear f r om a pl ace wher e i t i s f ound

t r oubl esome. Thi s may be done wher e wat er i s f ound

r est i ng upon cl ay, beneat h whi ch exi st s any st r at um of

Page 41 of 103

a por ous nat ur e ; f or i f an openi ng be made t hr ough

t he cl ay, t he wat er wi l l usual l y escape, and f i l t er

t hr ough t he i nf er i or st r at um. I n t hi s way many l ar ge

t r act s of l and have been dr ai ned ; and i t wi l l be ad-

vi sabl e i n al l cases, bef or e any expense be i ncur r ed i n

const r uct i ng dr ai ns or dr i vi ng headi ngs, t o consi der

whet her , f r om t he nat ur e of t he sub- st r at um, i t i s l i kel y

t hat a shaf t sunk down a f ew f eet wi l l ef i ' ect t he

pur pose r equi r ed.

The t hi r d and l ast case of dr ai nage t o be consi der ed

i s, wher e t he r oad has been r ai sed on embankment above

t he nat ur al sur f ace of t he gr ound. Her e i t i s obvi ous,

t hat t he onl y danger t o be appr ehended f r om wat er i s

t hat whi ch may be occasi oned by r ai n or snow f al l i ng

on t he sur f ace of t he r oad. Shoul d t he wat er succeed

i n penet r at i ng t hr ough t he upper cover i ng of t he r oad,

and si nk i nt o t he body of t he embankment , i t wi l l pass

downwar ds wi t hout doi ng much mi schi ef ; but i f t he

embankment be not composed of por ous mat er i al , but

63

consi st of cl ay, whi ch may per haps have been much

compr essed, and as i t wer e kneaded and puddl ed by

t he wheel s of car t s and waggons dur i ng t he f i l l i ng of

t he embankment , t he wat er wi l l not so r eadi l y si nk i nt o

i t , but be hel d up amongst t he boxi ng or r oad met al .

Under t hese ci r cumst ances, i t i s necessar y t hat some

ki nd of dr ai nage shoul d be pr ovi ded. I f t he r oad have

a l ongi t udi nal i ncl i nat i on, t he dr ai ns t o be f or med i n

t he r oad met al of t he embankment shoul d be of t he

ki nd cal l ed mi t r e dr ai ns ; t hat i s, t hey shoul d not be

f or med acr oss t he r oad at r i ght angl es t o i t s di r ect i on,

but shoul d be f or med obl i quel y f r om t he cent r e t o t he

si des, i n or der t hat t hey may have a f al l i n t he same

di r ect i on as t he r oad i t sel f . The mi t r e dr ai ns ar e

usual l y cut a f oot wi de and a f oot deep bel ow t he bed

of t he r oad, and f i l l ed wi t h cl ean st ones, of t he same

descr i pt i on as t hose descr i bed f or t he si de dr ai ns i n

cut t i ngs. Mi t r e dr ai ns, however , ar e onl y necessar y

whi l st t he r oad met al or cover i ng r emai ns l oose and

unbound ; because, when i t has once become har d and

sol i d, t he wat er f al l i ng on t he sur f ace wi l l not pene-

t r at e i nt o i t , but r un of l F t owar ds t he si des: hence I

shoul d never advi se t he f or mat i on of t hese dr ai ns,

except wher e heavy r ai ns ar e expect ed, bef or e t he r oad

met al can have t i me t o set and har den ; and even t hen,

as bef or e st at ed, t hey ar e onl y necessar y on embank -

ment s f or med of cl ay, whi ch has been r ender ed i m-

per vi ous t o wat er . I shoul d t hi nk i t possi bl e, i n al l

cases, t o l ay on t he r oad met al l i ng even on a cl ay

embankment , and t o cause i t t o set and become har d

bef or e i t can be i nj ur ed by r ai n ; and whenever t hi s can

be done t he mi t r e dr ai ns may be di spensed wi t h.

Suppose now t he r oad sur f ace t o be f or med har d and

sol i d, so t hat t he wat er whi ch f al l s on i t wi l l not si nk

i n, but r un of i " t owar ds t he si des ; i f t he r oad has been

04

Page 42 of 103

made wi t hout f oot pat h or ver ge, t he wat er wi l l of

cour se r un of f t he t op of t he embankment and down

t he si des of t he sl opes ; but i f on opposi t e si des of t he

car r i age- way a f oot pat h and ver ge have been f or med,

dr ai ns must be l ai d under t hese at i nt er val s, t o conduct

t he wat er f r om t he si des of t he r oad on t o t he sl opes.

These dr ai ns may be si mi l ar t o t hose descr i bed f or t he

r oad on a l evel wi t h t he gr ound sur f ace, and may be

pl aced at t he same i nt er val apar t , namel y, f or t y or f i f t y

yar ds. Fr om t he poi nt s wher e t hese dr ai ns open on

t he sl opes, i t i s an excel l ent pl an t o f or m paved chan-

nel s di r ect l y down t he sl opes, i n or der t o pr eser ve t he

l at t er , and pr event t he wat er f r om spr eadi ng over t hei r

sur f ace, and si nki ng i nt o t he embankment . These

paved channel s may be f or med wi t h any r ough pi t chi ng

st ones, and shoul d be made about t wo f eet wi de, wi t h

a concavi t y or di sh i n t he cent r e of about f our i nches ;

and t o add t o t he f i ni shed appear ance of t he sl opes,

t he si des of t hese channel s may be def i ned by a r ow of

gr ass sods, l ai d wi t h t he gr een swar d upper most .

G5

CHAPTER VI I .

On t he Means of compar i ng di f f er ent Roads, and of

est i mat i ng t he Ef f ect of I ncl i nat i ons, and t he ot her

Causes pr oduci ng r esi st ance t o Mot i on.

No pr et ence i s her e made of bei ng abl e t o af f or d t he

engi neer any i nf or mat i on i n t he pr act i ce of a par t of

hi s pr of essi on, whi ch i s commonl y execut ed wi t h so

much abi l i t y and j udgment , as t he l ayi ng down and

t r aci ng t hr ough a di st r i ct of count r y t he l i ne of a new

r oad. I t wi l l obvi ousl y be t r avel l i ng beyond t he l i mi t s

i n vi ew, t o ent er upon t he gener al engi neer i ng consi der a-

t i ons whi ch may pr esent t hemsel ves, t o det er mi ne t he

mer i t s and def ect s of par t i cul ar new l i nes, and f i nal l y

t o t ur n t he bal ance of opi ni on i n f avour of t hat one

whi ch i s f ound, upon i nvest i gat i on, t o possess t he

most deci si ve mer i t s. These consi der at i ons ar e, t o a

cer t ai n ext ent , si mi l ar and mut ual l y appl i cabl e i n t he

sever al cases of canal s, r ai l ways, and common r oads.

They i nvol ve t he necessi t y of l and sur veys, f r om whi ch

t he f eat ur es of t he count r y, i n r espect of pr oper t y and

popul at i on, must be accur at el y known and del i neat ed.

Sur veys, al so, of l evel s ar e absol ut el y necessar y, t hat

sect i ons of t he count r y may be made i n var i ous di r ec -

t i ons, t o show t he hei ght s of summi t s and dept hs of

val l eys t o be i nt er sect ed, and gener al l y t o det er mi ne

t he nat ur e of t he i ncl i nat i ons of whi ch t he new r oad i s

F

6G

t o consi st . The j udgment of t he engi neer i s f or med

Page 43 of 103

wi t h t hese dat a bef or e hi m ; and i n al l wor ks of i m-

por t ance t hat j udgment ought t o be based upon a

t hor ough pr act i cal exper i ence, ai ded by a per f ect know-

l edge and del i ber at e consi der at i on of al l t he var i ous

ci r cumst ances i n whi ch t he new wor k i s t o be pl aced,

or whi ch may be br ought t o bear upon i t s f ut ur e posi -

t i on. The at t empt t o l ay down any gener al r ul es on a

subj ect capabl e of such ext ended r ami f i cat i on, woul d

pr obabl y f ai l t o convey much usef ul i nf or mat i on ; but

wi t h a vi ew t o t he compar i son of r oads al r eady exi st -

i ng, and i n or der t o ar r i ve at some si mpl e means of

appr eci at i ng t he f or ce of dr aught r equi r ed on di f f er ent

r oads, and on di f f er ent par t s of t he same r oad, i t

may be usef ul t o consi der t he ef f ect s of gr avi t y and

f r i ct i on i n pr oduci ng i ncr ease or di mi nut i on of t he

dr aught .

The f or mer of t hese, namel y gr avi t y, i s a f or ce

ver y easi l y est i mat ed. On a l evel pl ane or hor i zont al

r oad, t he ent i r e wei ght of any car r i age i s suppor t ed by

t he r oad i t sel f , and t her ef or e t he movi ng power i s not

t axed t o suppor t any of t he wei ght ; hence i n t hi s case

t her e i s no r esi st ance what ever by r eason of gr avi t y,

t he onl y r et ar di ng f or ce bei ng t hat of f r i ct i on, or t he

r esi st ance t o mot i on occasi oned by t he r ugged uneven

sur f ace of t he r oad. On a pl ane i ncl i ned t o t he hor i zon,

t he ef l ect , wi t h r espect t o t he power of t r act i on r equi r ed,

i s t he same as i f t he wei ght be onl y par t i al l y suppor t ed

by t he r oad. The amount so suppor t ed i s equal t o t he

whol e wei ght , mi nus t hat por t i on of i t denot ed by t he

i ncl i nat i on of t he pl ane ; t hus on an i ncl i nat i on of 1 i n

30, expr essed by t he f r act i on - ^ \ , t he amount | g of t he

wei ght i s suppor t ed by t he r oad, and t he r emai ni ng - ^ ^ ^

has t o be suppor t ed by t he movi ng power . The conse-

67

quence i s t hat , cal l i ng t he nat ur al si ne of t he i ncl i na-

t i on of any pl ane t he quot i ent of t he hei ght di vi ded by

t he l engt h, i n t he case of a wei ght ascendi ng t he pl ane,

t he f or ce of t r act i on r equi r ed i s equal t o t he f r i ct i on

i ncr eased by t he pr oduct of t he wei ght mul t i pl i ed by t he

nat ur al si ne of t he i ncl i nat i on ; and i n t he case of a

wei ght descendi ng, t he f or ce of t r act i on r equi r ed i s

equal t o t he f r i ct i on di mi ni shed by t he same pr oduct .

The f r i ct i on of a car r i age movi ng on a r oad i s

expr essed by t hat wei ght whi ch, bei ng connect ed wi t h

i t , suspended over a pul l ey, and al l owed f r eel y t o de-

scend, wi l l dr ag t he car r i age al ong a l evel r oad. That

wei ght i s usual l y st at ed whi ch i n t hi s way i s capabl e

of dr aggi ng a t on ; and var i ous exper i ment s have been

made t o det er mi ne t he amount of t hi s wei ght , or t he

f r i ct i on of a t on on di f f er ent ki nds of r oad. Si r Henr y

Par nel l , i n hi s Tr eat i se on Roads, gi ves t he f ol l owi ng

t abl e :

Tabl e of Fr i ct i on. I n l bs. per t on.

On a wel l made pavement 33

On a br oken st one sur f ace, or ol d f l i nt r oad . . . 65

Page 44 of 103

On a gr avel r oad . . . 147

On a br oken st one r oad, wi t h a r ough pavement

f oundat i on 46

On a br oken st one sur f ace upon a bot t omi ng of con-

cr et e, f or med of Par ker ' s cement and gr avel . . 46

These r esul t s have been pr i nci pal l y der i ved f r om

exper i ment s wi t h Mr . McNei l ' s dynamomet er , and must

be under st ood as onl y appl i cabl e t o ver y sl ow vel oci t i es.

On al l sur f aces wher e t he f r i ct i on i s consi der abl e, t he

amount of t hi s r et ar di ng f or ce i ncr eases ver y much as

t he vel oci t y of t he movi ng body i ncr eases ; hence i n al l

exper i ment s on t hi s subj ect , t he r at e of t r avel l i ng at

whi ch t he f r i ct i on i s t aken, shoul d be par t i cul ar l y

not i ced, ot her wi se t he exper i ment can be of no ut i l i t y.

F 2

68

A ver y good pr act i cal met hod of det er mi ni ng t he f r i c -

t i on i s t o pl ace a car r i age, waggon, car t , or ot her

vehi cl e mount ed on wheel s, and wi t h axl es wel l gr eased,

upon a sl opi ng r oad, and ascer t ai n t he i ncl i nat i on on

whi ch t he vehi cl e wi l l j ust move f or war d by t he f or ce

of i t s own gr avi t y. At t hi s i ncl i nat i on, what ever i t

may be, t he f or ce of gr avi t y i s of cour se exact l y equal

t o t he f r i ct i on, because t he f or mer i s j ust capabl e of

over comi ng t he l at t er r esi st ance, and causi ng t he body

t o move. The i ncl i nat i on at whi ch t hi s ef f ect t akes

pl ace i s cal l ed t he angl e of r epose, or t he angl e of

f r i ct i on. Now t he f or ce of gr avi t y i s easi l y det er -

mi ned, bei ng, as bef or e st at ed, equal t o t he wei ght of

t he body mul t i pl i ed by t he i ncl i nat i on of t he pl ane ;

and t he f r i ct i on bei ng, i n t he case supposed, exact l y t he

same as t he f or ce of gr avi t y, i s of cour se det er mi ned

by t he same means. For exampl e : i f i t be f ound t hat

a car r i age wi l l j ust begi n t o move downwar ds on an

i ncl i nat i on of 1 i n 30, t he f r i ct i on of a t on wei ght on a

l evel r oad of t he same ki nd wi l l be equal t o 2240 x ^ V

= 74# l bs. The amount of f r i ct i on t hus f ound

3

'

ought t o cor r espond wi t h t hat whi ch woul d be i ndi cat ed

by t he dynamomet er , because i n bot h cases t he r at e of

mot i on woul d be ver y sl ow. As t he i ncl i nat i on of a

r oad i s usual l y expr essed by a f r act i on of whi ch t he

numer at or i s uni t y, t hi s f r act i on bei ng al so cal l ed t he

nat ur al si ne of t he angl e of i ncl i nat i on, t he r ul e f or

f i ndi ng t he f or ce of gr avi t y, by mul t i pl yi ng t he wei ght

by t he f r act i on expr essi ng t he i ncl i nat i on of t he pl ane,

i s of cour se t he same t hi ng as t o di vi de t he wei ght by

t he l engt h of t he pl ane cor r espondi ng t o a r i se of 1.

Hence put t i ng t he wei ght = W, and t he i ncl i nat i on of

t he pl ane =

, t he si mpl e f or mul a

wi l l expr ess t he

Page 45 of 103

f or ce of gr avi t y of t he wei ght JV. Thi s amount

has

69

t o be added t o t he f r i ct i on i n t he case of a wei ght

bei ng dr awn up t he phme, and deduct ed f r om i t i n t he

case of a wei ght descendi ng t he pl ane. Pr obabl y, how-

ever , t he most usef ul f or m i n whi ch t o exhi bi t t he ef f ect

of var i ous i ncl i nat i ons wi t h r espect t o t he power of

t r act i on r equi r ed, wi l l be t o det er mi ne t he wei ght s

whi ch, on a l evel r oad of t he same ki nd, wi l l r equi r e

exact l y t he same power of t r act i on. Thi s i s ext r emel y

si mpl e: f or i f F be t he f r i ct i on of a gi ven wei ght W, and

w

as bef or e be t he f or ce of gr avi t y, we have t he whol e

r esi st i ng f or ce = i ^ +

f or t he ascendi ng pl ane, and

F f or t he descendi ng pl ane. Then t o f i nd t he

wei ght whi ch t he power F +

i s capabl e of movi ng

on a l evel pl ane, we have t hi s pr opor t i on, F : W : - .

F +

: W' t he wei ght r equi r ed, hence W + y^ = W' .

I n t he same way f or a descendi ng pl ane, we have F :

W : : F- ^ : W; hence W - ~= W, t he wei ght

whi ch can be moved on a l evel wi t h t he same exer t i on

of f or ce as t hat r equi r ed t o move t he wei ght W on

a descendi ng pl ane, whose i ncl i nat i on i s

On t hi s

pr i nci pl e t he f ol l owi ng t abl e has been const r uct ed; but

i t must be obser ved, t hat t he val ue of F, whi ch i n

t he t abl e i s assumed at 112 l bs. , must be det er mi ned

f or any par t i cul ar r oad on whi ch t he r esi st ance has t o

be cal cul at ed. For r oads wher e t he f r i ct i on ei t l i er ver y

much exceeds or f al l s shor t of t hi s amount , t he l ast

col umn onl y wi l l be of use i n savi ng t he l abour of

cal cul at i on; because t hi s shows t he power r equi r ed

t o over come t he f or ce of gr avi t y al one, i ndependent

of f r i ct i on, on t he sever al i ncl i nat i ons f r om 1 i n 300

up t o 1 i n 5.

Page 46 of 103

70

Tabl e of Resi st ances and Equi val ent Loads, wher e t he Fr i ct i on

i s =

or 112 l bs. per Ton.

20 ^

Rat e of

I ncl i nat i on.

Resi st ance of one t on,

or power r equi r ed t o

dr aw one t on when

t he f r i ct i on i s =

-

or 112 l bs. per t on.

Eci ui val ent l oad on t he

l evel , or l oad whi ch

r equi r es t he same

power of dr aught as

one t on.

Resi st ance

ar i si ng f r om

gr avi t y al one,

or val ue of

t he f r act i on

2240

r

On t he as-

cendi ng pl ane.

On t he de-

scendi ng pl ane

On

t heascendi ng

pl ane.

Page 47 of 103

On t he descendi ng

pl ane.

l bs.

I ba.

Ton

l bs.

Ton. l bs.

l bs.

1 i n 300

119- 47

104 - 53

149- 3

0, 2090

7

7 - 4667

, 295

119 - 59

104 - 41

151 - 9

Page 48 of 103

0, 2088

- 1

7 - 5932

, 290

119- 72

104 - 28

154 - 5

0. 2085

- 5

7 - 7241

, 285

119- 86

104 14

157- 2

0. 2082

- 8

7 - 8596

, 280

Page 49 of 103

120 - 00

104 - 00

160- 0

0. 2080

0

8 - 0000

, 275

120- 15

103- 85

162 - 9

0. 2077

- 1

8 1454

, 270

120 - 30

103 - 70

165- 9

0, 2074

Page 50 of 103

1

8 - 2963

, 265

120 - 45

103 - 55

169

0. 2071

8 - 4528

, 260

120 - 62

103 - 38

172- 3

0. 2067

7

8- 6154

, 255

120 - 78

Page 51 of 103

103 - 22

175- 7

0. 2064

- 3

8 - 7843

, 250

120 - 96

103 04

179- 2

0. 2060

8

8 - 9600

, 245

121 14

102 - 86

182 - 8

0, 2057

2

Page 52 of 103

9 1428

, 240

121 - 33

102 - 67

186- 7 0. 2053

3

9 - 3333

, 235

121 - 53

102 - 47

190 - 6 0. 2049

4

9- 5319

, 230

121 - 74

102 - 26

194- 8 0. 2045

2

Page 53 of 103

9 - 7391

, 225

121 - 96

102 04

199- 1 10, 2040

9

9 - 9555

, 220

122- 18

101 82

203 - 6 i 0. 2036

4

10- 1818

, 215

122 - 42

101- 58

208 - 4

Page 54 of 103

0. 2031

6

10- 4186

, 210

122 - 67

101 - 33

213- 3

0, 2026

7

10 - 6667

, 205

122 - 93

101 - 07

218- 5

0. 2021

5

10 - 9268

, 200

Page 55 of 103

123 - 20

100- 80

224 - 0

0. 2016

11- 2000

, 195

123 - 49

100- 51

229 - 7

0. 2010

- 3

11 - 4872

, 190

123- 79

100- 21

235 - 8

0. 2004

Page 56 of 103

2

11 - 7895

, 185

124- 11

99- 89

24' 2 - 2

0. 1997

8

12- 1081

, 180

124 - 44

99- 56

248 - 9

0, 1991

1

12 - 4444

, 175

124 - 80

Page 57 of 103

99 - 20

256

0, 1984

12 - 8000

, 170

125- 18

98 - 82

263 - 5

0. 1976

5

13- 1765

, 1( ) 5

125 - 58

98- 42

271 - 5

0, 1968

5

Page 58 of 103

13- 5758

, 160

126- 00

98- 00

280 - 0

0, 1960

14 - 0000

, 155

126 - 45

97 - 55

289 - 0

0, 1951

14- 4516

, 150

126 - 93

97 - 07

Page 59 of 103

298 - 7

0, 1941

3

14 - 9333

, 145

127 - 45

96 - 55 1 .

309- 0

0. 1931

15- 4483

, 140

128 - 00

96 - 00 1.

320 - 0

0, 1920-

16 - 0000

, 135

Page 60 of 103

128 - 59

95 - 41

331 - 8

0, 1908 -

2

16 - 5926

, 130

129 - 23

94 - 77

3 14

( >

0. 1895

4

17- 2308

, 125

129- 92

94 - 08

358 - 4

0. 1881-

Page 61 of 103

6

17 - 9200

, 120

130

( ! 7

93 - 33

373- 3

0. 1866-

7

18 - ( ; ( ) ( J7

, 115

131 - 48

92 - 52

389 - 6

0. 1850-

4

19- 4783

, no

132- 36

Page 62 of 103

91 - 61

407 - 3

0. 1832

7

20 - 3636

, 105

133 - 33

00- 67

4- 26 - 7

0. 1813- 3 j

21 - 3333

71

Tabl e of Resi st ances and Equi val ent Loads

cont i nued.

Rat e of

I ncl i nat i on.

Resi st ance of one t on,

or power r equi r ed t o

dr aw one t on when

Jf T

t he f r i ct i on i s = - 53-

or 112 l bs. per t on.

Page 63 of 103

Equi val ent l oad on t he

l evel , or l oad whi ch

r equi r es t he same

power of daught as

one t on.

Resi st ance

ar i si ng f r om

gr avi t y al one,

or val ue of

t he f r act i on

2240

On t he as-

cendi ng pl ane.

On t he de-

scendi ng pl ane_

On t he ascendi ng

pl ane.

On t he descendi ng

pl ane.

r

l bs.

l bs.

Ton. l bs.

Ton. l bs.

l bs.

1 i n 100

Page 64 of 103

134 - 40

89

60

1. 448^ 0

0. 1792 - 0

22

4000

, , 95

135 - 58

88

- 42

1. 471 6

0. 1768 - 4

23

5789

, , 90

136 - 89

87

11

1. 497- 8

0. 1742 2

Page 65 of 103

24

8889

, , 85

138 - 35

85

65

1. 527 1

0. 1712 - 9

26

3529

, , 80

140 - 00

84

00

1. 560^ 0

0. 1680 - 0

28

0000

, , 75

141 - 87

82

13

Page 66 of 103

1. 597 3

0. 1642- 7

29

8667

, , 70

144 - 00

80

00

1. 640

0. 1600- 0

32

0000

, , 65

146 - 46

77

54

1. 689- 2

0. 1550- 8

34

4615

, , 60

Page 67 of 103

149- 33

74

67

1. 746 7

0. 1493 - 3

37

3333

, , 55

152 - 73

71

27

1. 814 5

0. 1425

S

40

7273

, , 50

156 - 80

67

20

1. 896

0. 1344

Page 68 of 103

44

8000

, , 45

161- 78

62

22

1. 995 6

0. 1244 4:

49

7778

, , 40

168 - 00

56

00

1. 1120

0. 1 120

O

56

0000

, , 35

176 - 00

48

00

Page 69 of 103

1. 1280^ 0

0. 960- 0

64

0000

, , 30

186 - 67

37

33

1. 1493 3

0. 746- 7

74

6667

, , 29

189- 24

34

76

1. 1544 8

0. 685^ 2

77

2414

, , 28

Page 70 of 103

192 - 00

32

00

1. 1600 - 0

0. 640

80

0000

, . 27

194 - 96

29

04

1. 1659 3

0. 580- 7

82

9630

, , 26

198 15

25

85

1. 17- 23 1

0. 516- 9

Page 71 of 103

86

1538

, , 25

201 - 60

22

40

1. 1792

0. 448 - 0

89

6000

, , 24

205 - 33

18

67

1. 1866^ 7

0. 373 3

93

3333

, , 23

209 - 39

14

61

Page 72 of 103

1. 1947 8

0. 292 2

97

3913

, , 22

213 - 82

10

18

1. 2036 - 4

0. 203

O

101

8182

, , 21

218- 67

5- 33

1. 2133 - 3

0. 106- 7

106

6667

, , 20

2- 24 - 00

Page 73 of 103

2. 000- 0

112

0000

, , 19

229 - 89

2. 117- 9

117

8947

, , 18

236 - 44

2. 248- 9

1- 24

4444

, , 17

Page 74 of 103

243 - 76

2. 395 3

131

7647

, , 16

252 - 00

2. 560- 0

140

0000

, , 15

261 - 33

2. 746- 7

149

Page 75 of 103

3333

, , 14

272 - 00

2. 960- 0

160

- 0000

, , 13

' 284 - 31

2. 1 206^ 2

172

3077

, , 12

298 - 67

2. 1493 - 3

Page 76 of 103

186

6667

, , 11

315 - 64

2. 1832 - 7

203

6364

, , 10

336 - 00

3. 000- 0

224

0000

, , 9

360 - 89

Page 77 of 103

3. 491- 8

248

8889

, , 8

392 - 00

3. 1120

280

0000

, , 7

432 - 00

3. 1920 - 0

320

- 0000

, , 6

485 - 33

Page 78 of 103

4. 746- 7

373

- 3333

, , 5

560 - 00

5. 000- 0

448

OOOO

72

The const r uct i on and use of t hi s t abl e ar e so si mpl e

as t o r equi r e ver y l i t t l e expl anat i on. The 2nd and 3r d

col umns show t he act ual amount of power r equi r ed t o

dr ag- a wei ght of one t on, on t he sever al ascendi ng and

descendi ng pl anes, of whi ch t he i ncl i nat i ons ar e gi ven

i n t he 1st col umn. These amount s of power bei ng

known, t he 4t h and 5t h col umns, showi ng t he l oad

whi ch can be dr awn on a l evel , by t he same power as

t hat necessar y t o dr aw a t on r espect i vel y up and down

t he sever al i ncl i nat i ons i n t he 1st col umn, ar e easi l y

cal cul at ed by means of t he pr opor t i on al r eady men-

t i oned. Wher e t he l oad has t o be dr awn up t he i n-

cl i nat i on, i t i s evi dent t hat mor e power must be exer t ed

t han i s necessar y t o dr aw t he same l oad on a l evel ;

hence t he amount s of power i n t he 2nd col umn ar e al l

mor e t han 112 l bs. , because t hi s i s t he power r equi r ed t o

dr aw a t on on t he l evel . Agai n, wher e t he l oad i s

descendi ng t he i ncl i nat i on, a l ess amount of power i s

necessar y t han on a l evel ; hence t he amount s i n t he 3r d

col umn ar e al l l ess t han 112 l bs. I t f ol l ows al so, f r om

t he nat ur e of t he f or mul a FT

, by whi ch t hese amount s

have been cal cul at ed, t hat on any gi ven i ncl i nat i on t he

amount of power r equi r ed t o ascend, t he amount r e-

Page 79 of 103

qui r ed on a l evel , and t he amount r equi r ed t o descend

t he gi ven i ncl i nat i on, ar e t hr ee quant i t i es havi ng a

common di l Ver ence, and t her ef or e i n ar i t hmet i cal pr o-

gr essi on. Thi s i s f ur t her evi dent , i n consi der i ng t hat

t he excess r equi r ed t o ascend i s equal t o t he di mi ni shed

quant i t y suf f i ci ent i n descendi ng. And si nce t he equi -

val ent l oads whi ch can be dr awn on a l evel ar e

pr opor t i onal t o t he power expended, t he same pr oper t y

obt ai ns wi t h r egar d t o t l i em :

f or exampl e, t he l oad

whi ch can be dr awn on a l evel wi t h t he same power

r ecj ui r ed t o dr aw a t on wei ght up any gi ven i ncl i nat i on,

and t he l oad whi ch can be dr awn on a l evel wi t h t he

same power r equi r ed t o dr aw t he t on wei ght down t he

73

gi ven i ncl i nat i on, ar e t he ext r emes of an ar i t hmet i cal

pr ogr essi on, of whi ch one t on i s t he mean or mi ddl e

t er m. These pr oper t i es may be shor t l y expr essed al ge-

br ai cal l y: t hus, l et P be t he power r equi r ed t o dr aw

t he l oad TFup any gi ven i ncl i nat i on, and p t he power

t o dr aw t he same l oad down t he i ncl i nat i on ; al so, l et

F, as bef or e, be t he f r i ct i on of t he l oad W on &. \ e\ e\ ,

t hen we have - ^

= F. Fur t her , l et L be t he equi va-

l ent l oad on a l evel f or an ascendi ng pl ane, and / t he

equi val ent l oad f or a descendi ng pl ane of t he same i ncl i -

nat i on, t hen -

= W.

r t i s obvi ous, i f we know by exper i ment t he amount s

of power P and p r equi r ed t o dr aw any wei ght r espect -

i vel y up and down any i ncl i nat i on, t hat we can at once

det er mi ne t he f r i ct i on of t hat wei ght , or t he power r e-

qui r ed t o dr aw i t on a l evel , and al so t he r at e of i ncl i na-

t i on f or whi ch t he amount s Pandphavebeen ascer t ai ned.

Wi t hout supposi ng t hat t hi s met hod of f i ndi ng t he i n-

cl i nat i ons of a r oad, wi l l ever super sede t he mor e accu-

r at e met hod of l evel l i ng f or t hat pur pose, i t may yet

of t en be f ound usef ul t o appr oxi mat e i n t hi s way. We

have al r eady seen t hat

^ ~ ^ > ^ ^ ^ ^ si nce P i s t he

whol e power of dr aught up t he pl ane, and F i s t hat

par t of t he whol e power whi ch ar i ses f r om f r i ct i on, i t i s

evi dent t hat P

F i s equal t o t he r esi st ance ar i si ng

f r om t he f or ce of gr avi t y on t he i ncl i nat i on. Now

t he f or ce of gr avi t y i s al so equal t o

; hence put t i ng

t hese t wo expr essi ons equal t o each ot her , we have onl y

t o f i nd f r om t he equat i on P

P =

, i n whi ch al l t he

quant i t i es ar e gi ven except r , t he val ue of t hi s unknown

quant i t y expr essi ng t he i ncl i nat i on of t he pl ane. Sol v -

i ng t hen t he above equat i on, we have r ( P

F) = W,

and ^ _p =r , t he r at e of i ncl i nat i on. An exampl e of

t hi s may be t aken f r om t he t abl e:

Suppose t he amount s

of power r equi r ed t o dr aw a t on wei ght up and down a

74

cer t ai n i ncl i nat i on be r espect i vel y 128 and 9l > l bs. t hen

-

= - ^ = 112 = F t he f r i ct i on as i n t he t abl e.

And r i i ^ = ^ f i ^ = 140 = r ; t hat i s, t he i ncl i nat i on

of t he pl ane f or whi ch t hese amount s of power have been

det er mi ned, i s 1 i n 140, as i n t he t abl e. I t i s easy when

Page 80 of 103

t he i ncl i nat i on of a pl ane i s gi ven t o ascer t ai n t he di f -

f er ence of l evel bet ween any t wo poi nt s on i t s sur f ace,

pr ovi ded we know t he di r ect di st ance bet ween t hem

measur ed i n t he l i ne of t he pl ane : t hus, i f an i ncl i nat i on

r i se 1 i n r , i t i s evi dent t hat i n each uni t of l engt h t he

r i se wi l l be

; hence i f we di vi de any gi ven l engt h on

t he pl ane by t he denomi nat or of t he f r act i on expr essi ng

t he r at e of i ncl i nat i on, t he quot i ent wi l l be t he di f f er ence

of l evel of t he t wo poi nt s at t he ext r emi t i es of t hat

l engt h.

I n al l r oads t her e i s a cer t ai n angl e of i ncl i nat i on

on whi ch i t wi l l r equi r e no power t o cause a wei ght t o

descend. Thi s has been al r eady ment i oned under t he

name of t he angl e of f r i ct i on ; and i t f ol l ows f r om t he

nat ur e of t he r el at i on exi st i ng on ever y pl ane, bet ween

t he power r equi r ed t o descend and t hat r equi r ed t o

ascend, t hat wher e t he power t o descend i s equal t o

zer o, or wher e p =0, t he power r equi r ed t o ascend i s

equal t o 2 F or doubl e t he f r i ct i on. But wher e t he

val ue of j t j becomes negat i ve or l ess t han not hi ng, t hat

i s, wher e

i s gr eat er t han F, t he amount of power r e-

qui r ed on t he descent bei ng al so l ess t han not hi ng, has

no l onger t o be cal cul at ed. I n f act , wher e t he pl ane i s

of gr eat er i ncl i nat i on t han t he angl e of f r i ct i on, t he l oad

i n descendi ng acqui r es an accel er at i ng f or ce, whi ch i f

not checked woul d ur ge i t downwar ds t oo r api dl y.

Hence i t i s usual i n such a case t o i ncr ease t he amount

of r et ar di ng f or ce act ual l y occasi oned by f r i ct i on, and

f or t hi s pur pose t he br eak or ski d i s appl i ed

t he i n-

cl i nat i on at whi ch i t becomes necessar y t o use t he

75

br eak, or i n ot her wor ds t o l ock t he wheel , bei ng pr o-

per l y speaki ng t he angl e of f r i ct i on. I t i s obvi ous t hat

t hi s angl e i s not t he same f or al l ki nds of r oad, si nce i t

depends ent i r el y on t he amount of t he f r i ct i on i t sel f ; t hus

i n t he t abl e wher e t he f r i ct i on of one t on i s t aken at ^ V?

or 112 l bs. , t he angl e of f r i ct i on i s t hat whi ch i s made

wi t h t he hor i zon by a pl ane whose i ncl i nat i on i s 1 i n 20 ;

and i n gener al t er ms, i f F be t he amount of f r i ct i on f or

any wei ght W, t he i ncl i nat i on of t he pl ane f or mi ng t he

angl eof f r i ct i on, wi l l be

.

I n or der t o i l l ust r at e t he ef f ect of st eep i ncl i nat i ons,

i t may be usef ul agai n t o r ef er t o t he pr ecedi ng t abl e,

wher e we f i nd f or i nst ance t hat t he l oad on a l evel , equi -

val ent t o one t on ascendi ng an i ncl i nat i on of 1 i n 20,

i s j ust doubl e or t wo t ons ; and i f t he r oad become as

st eep as 1 i n 10, t he equi val ent l oad i s t hr ee t i mes as

gr eat or t hr ee t ons ; t hus, t he i ncl i nat i on of 1 i n 10 r e-

qui r es 50 per cent , mor e power t han t he i ncl i nat i on of

1 i n 20. Agai n, t he i ncl i nat i on of 1 i n 60 r equi r es a

power equi val ent t o t hat whi ch woul d dr aw 1 t on 747 l bs.

on a l evel ; and as t hi s equi val ent l oad bear s t he same

pr opor t i on t o t wo t ons as t hi s l at t er l oad bear s t o

t hr ee t ons, i t i s evi dent t hat t he i ncl i nat i on of 1 i n 10

has t he same r el at i on t o 1 i n 20 as t hi s l at t er has t o

1 i n 60. Next , as t o t he act ual di f f er ences of dr aught ,

i t appear s, t hat i f a hor se can j ust dr aw one t on upon a

l evel r oad, i t wi l l r equi r e t wo hor ses t o ascend wi t h t hi s

Page 81 of 103

wei ght an i ncl i nat i on of 1 i n 20, and t hr ee hor ses t o

ascend an i ncl i nat i on of 1 i n 10. Hence t he ext r emes

of power r equi r ed, wi t hi n t he shor t r ange of 1 i n 10 and

1 i n 20, pr esent as wi de a di f f er ence as i n t he l ong r ange

bet ween 1 i n 10 and a per f ect l y hor i zont al pl ane.

When i t i s necessar y t o cal cul at e t he dr aught r e-

qui r ed on a r oad wher e t he f r i ct i on has been det er -

mi ned at any ot her amount t han 112 l bs. , t he 6t h or

76

l ast col umn of t he t abl e must be empl oyed. Thus, i f

t he f r i ct i on on a r oad shoul d be f ound, f or exampl e, t o

be 150 l bs. per t on, and i t be necessar y t o f i nd t he power

of dr aught r equi r ed on an i ncl i nat i on of 1 i n 80 :

Take

f r om t he t abl e t he amount i n t he ( i t h col umn opposi t e

t o 1 i n 80, t hi s amount whi ch i s 28 l bs. bei ng- t he f or ce of

gr avi t y al one. Then 150 + 28 = 178 l bs. i s t he whol e

power r equi r ed t o dr aw a t on up t he i ncl i nat i on, and

150

28 = ] 22 l bs. i s t he amount r equi r ed t o dr aw t he

wei ght down t he i ncl i nat i on. Fur t her . ??12_i L_i i i - =

* 150

2658 l bs. t he wei ght whi ch can be dr awn on a l evel by

t he power of 178 l bs. , and ' ^ ' ^ ^ ^ ^ ^ ^ ^ ^ =1 822 l bs. t he wei ght

whi ch can be dr awn on a l evel by t he power of 122 l bs.

The 6t h col umn of t he t abl e wi l l al so be usef ul i f we

wi sh t o ascer t ai n t he angl e of f r i ct i on cor r espondi ng t o

di f i ' er ent amount s of dr aught on r oads. For exampl e,

i f on any r oad t he f r i ct i on or r esi st ance on a l evel be

equ^ l t o 80 l bs. per t on, t he angl e of f r i ct i on f or t hi s r oad

wi l l be 1 i n 28. And so of any ot her amount s i n t he 6t h

col umn, t he r at es of i ncl i nat i on opposi t e t o t hem i n t he

f i r st col umn bei ng r espect i vel y t he number s whi ch ex-

pr ess t he cor r espondi ng angl es of f r i ct i on.

I n t he pr ecedi ng exposi t i on of t he met hods of est i -

mat i ng t he f or ces of f r i ct i on and gr avi t y on di f f er ent

r oads, i t must be under st ood t hat t hese f or ces expr ess

onl y t he power r equi r ed t o set i n mot i on a gi ven wei ght

under t he ci r cumst ances f or whi ch t hat power i s cal -

cul at ed. I n or der t o know t he whol e power r equi r ed

t o dr aw a gi ven wei ght al ong any l engt h of pl ane,

i ncl i ned or hor i zont al , we must mul t i pl y t he f or ce r e-

qui r ed t o move i t by t he l engt h of t he pl ane i t sel f , and

t he pr oduct wi l l l ) e t he whol e power r equi r ed. Thi s

must be evi dent i f we consi der t hat t he f or ce r equi r ed

t o set i n mot i on any l oad pl aced on a cer t ai n pl ane, i s

t hat wei ght whi ch hangi ng over a pul l ey wi l l j ust cause

77

t he l oad t o move ; and i f we concei ve t he l oad t o ad-

vance on t he pl ane any gi ven l engt h, t hi s advance must

be pr oduced by a cor r espondi ng and equal descent of

t he at t ached wei ght . Hence, i f a power P be r equi r ed

t o move a gi ven l oad on a pl ane 500 f eet l ong, t he whol e

f or ce r equi r ed t o move t he l oad f r om one end of t he

Page 82 of 103

pl ane t o t he ot her i s = 500 P; t hat i s, t he f or ce i s equal

t o t he wei ght P r ai sed 500 f eet hi gh, or whi ch i s t he

same t hi ng, t o t he wei ght 500 P r ai sed 1 f oot hi gh.

I n appl yi ng t he pr i nci pl es whi ch have now been

l ai d down, t o det er mi ne t he compar at i ve mer i t s of t wo

or mor e l i nes of r oad, i t wi l l be necessar y t o comput e

f or each i ncl i nat i on t he act ual power r equi r ed t o ascend

and descend wi t h a gi ven wei ght , and i t woul d seem at

f i r st si ght , t hat t he aggr egat e or t ot al of t hese amount s

woul d af i br d an expr essi on by whi ch t o i ndi cat e t he

compar at i ve mer i t of any l i ne of r oad. I t wi l l be f ound,

however , i n f ol l owi ng out t he consequences of some of

t he pr oposi t i ons l ai d down i n t he pr ecedi ng pages, t hat

t hi s expr essi on, al t hough per f ect l y accur at e, as cont ai n-

i ng t he act ual amount s of f or ce t o be exer t ed on each

pl ane t hr oughout t he r oad, wi l l yet f ai l i n a r emar kabl e

degr ee t o est abl i sh t he absol ut e super i or i t y of one l i ne

over anot her , al t hough t he power on t he f or mer may be

unquest i onabl y l ess i n amount t han t hat r equi r ed on

t he l at t er . I n i l l ust r at i on of t hi s except i on, i t wi l l be

necessar y t o r ever t t o t hat r el at i on subsi st i ng bet ween

t he t hr ee amount s of power exer t ed i n ascendi ng any

gi ven pl ane, i n movi ng on a l evel , and i n descendi ng t he

gi ven pl ane. I t has al r eady been obser ved, t hat t hese

t hr ee quant i t i es ar e i n ar i t hmet i cal pr ogr essi on, and t he

expr essi on al r eady made use of , namel y,

^ - ^ = F,

exhi bi t s t he f ol l owi ng r esul t ; t hat t he hal f sum of t he

amount s of power r equi r ed t o ascend and descend a

gi ven i ncl i nat i on, i s exact l y equal t o t he power r equi r ed

78

t o move over a l evel pl ane equal i n l engt h t o t he i n-

cl i nat i on i t sel f . The same pr oposi t i on may al so be

expr essed i n ot her wor ds, t hus:

t hat t o ascend and

descend a gi ven i ncl i nat i on, r equi r es t he same power as t o

t r avel backwar ds and f or war ds over a l evel pl ane equal

i n l engt h t o t he i ncl i nat i on.

Bef or e pr oceedi ng t o t he consequences of t hi s doc -

t r i ne i t i s necessar y t o not i ce, t hat i t no l onger hol ds

t r ue when t he angl e of i ncl i nat i on of t he gi vel i pl ane

exceeds t he angl e of f r i ct i on f or t he r oad i n quest i on.

I t i s evi dent t hat on al l pl anes wher e t he car r i ages wi l l

descend by t he f or ce of t hei r own gr avi t y, t he expr essi on

above used i s no l onger cor r ect ; because, what ever be

t he i ncl i nat i on of t he pl ane t he onl y val ue of j ? i s ;

and as P i ncr eases wi t h each i ncr ease i n t he r at e of

i ncl i nat i on, i t wi l l at once be obvi ous, t hat t o ascend and

descend any pl ane f or mi ng wi t h t he hor i zon a gr eat er

angl e t han t he angl e of f r i ct i on, r equi r es mor e power

t han t o t r avel backwar d and f or war d t he same di st ance

on a l evel pl ane. I t wi l l t her ef or e be under st ood, wi t h

r espect t o t he pr oposi t i on est abl i shi ng t hat an equal

amount of power i s r equi r ed t o t r avel up and down

an i ncl i nat i on, and t o t r avel doubl e t he l engt h of t he

i ncl i nat i on on a l evel , t hat t hi s appl i es onl y t o pl anes

of l ess i ncl i nat i on t han t hat f or med by t he angl e of

f r i ct i on.

We ar e now t o consi der t he ext ent t o whi ch an

Page 83 of 103

expr essi on of power l eadi ng t o such a r esul t , may be

used as a means of compar i ng t he mer i t s of di f f er ent

r oads. Wi t h t hi s vi ew we ar e t o bear i n mi nd t he

nat ur e of t he power whi ch has t o be empl oyed, i n over -

comi ng t he sever al r esi st ances t hat may be det er mi ned

by cal cul at i on. Thi s power on t he common r oads i s

gener al l y conf i ned t o t he l abour of hor ses; and when,

wi t h r ef er ence t o t hi s speci es of power , we asser t t he

f 9

pr oposi t i on as t o t he equal i t y of f or ce r equi r ed, i t be-

comes per haps mor e i r r econci l eabl e wi t h t he knowl edge

der i ved f r om ever y- day exper i ence, t han when appl i ed

t o any ot her descr i pt i on of power what ever . Thus, t o

asser t t hat t he l abour of t r avel l i ng al ong a mi l e of r oad

on whi ch i s a summi t 100 f eet hi gh r equi r es no mor e

power t han t o t r avel over a mi l e of l evel r oad, appear s

ver y i nconsi st ent wi t h gener al l y r ecei ved opi ni ons ; and

yet t hi s asser t i on i s st r i ct l y i n accor dance wi t h t he

gener al pr oposi t i on ; because, i f t he summi t be pl aced

hal f way t he i ncl i nat i on on each si de wi l l be 1 i n 26,

whi ch f or an amount of f r i ct i on = - ^ ^ - ^ i s a f l at t er i ncl i na-

t i on t han t he angl e of f r i ct i on. I t wi l l t her ef or e be

necessar y t o i nt r oduce i nt o t he expr essi on f or t he act ual

mechani cal f or ce t o be exer t ed, some modi f i cat i ons, i n

or der t o r ender t he r esul t s mor e near l y coi nci dent wi t h

t hose of known exper i ence. I n t he f i r st pl ace, t he hor se

ascendi ng an i ncl i nat i on has t o r ai se hi s own wei ght i n

addi t i on t o t he l oad, and t he power t hus expended must

of cour se be added t o t hat necessar y f or t he l oad.

Agai n, i n descendi ng, i t i s pr obabl e t hat i t r equi r es j ust

as much exer t i on t o t r anspor t hi s wei ght as on a l evel .

Now t he addi t i onal power r equi r ed t o car r y t he wei ght

of a hor se up an i ncl i nat i on, i s evi dent l y equal t o hi s

whol e wei ght mul t i pl i ed by t he hei ght of t he i ncl i na-

t i on; and i n f act , t he power r equi r ed f or t hi s pur pose i s

i n no r espect di f f er ent except i n amount f r om t hat r e-

qui r ed t o r ai se t he l oad dr awn by t he hor se. Hence, i t

wi l l be pr oper i n det er mi ni ng t he r esi st ance of a l oad

t o be dr awn up any i ncl i nat i on, t o consi der t he

wei ght of t he hor se i t sel f as a par t of t he l oad. Thi s,

i f we assume t he wei ght of a hor se at l Ocwt . , or hal f a

t on, and suppose t he l oad t o be dr awn i s one t on, t he

amount s expr essi ng i n t he t abl e t he r esi st ances ar i si ng

f r om gr avi t y must be i ncr eased 50 per cent , f or t he

80

upwar d dr aught . The ot her modi f i cat i ons whi ch i t mi ght

be pr oper t o i nt r oduce, ar e t hose ar i si ng f r om t he di s -

advant ageous way i n whi ch t he muscul ar power of a

hor se i s exer t ed, bot h i n ascendi ng and descendi ng

i ncl i ned pl anes. The act ual ef f ect of t hi s dr awback i n

di mi ni shi ng t he per f or mance of hor ses, i s a subj ect of

whi ch t he el uci dat i on depends ent i r el y on exper i ment .

We have seen i n t he pr ecedi ng pages, t hat t he mecha-

ni cal power r equi r ed t o dr aw any gi ven wei ght , f i r st up

an i ncl i nat i on and t hen down agai n, i s pr eci sel y t he

same as t hat r equi r ed t o dr aw t he wei ght t o and f r o

Page 84 of 103

on a l evel of equal l engt h wi t h t he i ncl i ned pl ane. We

may be cer t ai n, t her ef or e, t hat i f a st eam- engi ne, or any

ot her machi ne, wer e er ect ed at t he t op of a sl opi ng

pl ane, i n or der t o dr aw t he l oad up and down t he pl ane,

t he power expended woul d be pr eci sel y t he same as on

a l evel . We ar e not however t o suppose, t hat i t woul d

be f ound so advant ageous even t o empl oy machi ner y t o

wor k an i ncl i ned pl ane i n t hi s way as i t woul d be t o

wor k on a l evel by t he same means ; yet we know per -

f ect l y wel l t hat i n ei t her way t he same mechani cal

power i s expended. But on t he ot her hand exper i ence

ver y pl ai nl y t eaches, t hat a hor se cannot , wi t h t he same

ease or wi t h onl y t he same exer t i on of f or ce, dr aw a

l oad f i r st up and t hen down any i ncl i nat i on what ever , as

he coul d on a l evel of t he same l engt h. One r eason why

a gr eat er exer t i on i s r equi r ed on t he sl opi ng pl ane we

have al r eady assi gned

namel y, because hi s own wei ght

has t hen t o be r ai sed as wel l as t he l oad ; but i t i s al so

cer t ai n t hat t her e ar e some ot her consi der at i ons con-

nect ed wi t h t he physi cal st r uct ur e of t he hor se, whi ch

i ncr ease yet mor e t he exer t i on r equi r ed on sl opi ng

pl anes. Her e t hen i s t he necessi t y f or exper i ment :

I t i s r equi r ed t o know what i s t he cf l ' ect i ve per f or mance

of a hor se on di l l er cnt i ncl i nat i ons, as compar ed wi t h

81

t hat on a l evel . The det er mi nat i on of t hi s pr obl em

cer t ai nl y pr esent s some di f f i cul t y, and yet i n no ot her

way can we st r i ct l y pr onounce on t he mer i t of a r oad

wi t h r ef er ence t o t he act ual ki nd of power whi ch i s t o

be used upon i t .

The mechani cal expr essi on f or t he amount of power

r equi r ed, wi l l enabl e any one t o j udge t o a much gr eat er

ext ent on t hi s subj ect t han he coul d i n t he absence of

any i nvest i gat i on. For exampl e: i f we know t hat a

r oad has an i ncl i nat i on of 1 i n 28 f or t he l engt h of a

mi l e, and t hat i t t hen descends by an i ncl i nat i on on t he

ot her si de, i t wi l l appear f r om t he t abl e t hat dur i ng

t hi s mi l e t he hor se must dr aw wi t h a f or ce capabl e of

dr awi ng 1 t on 1600 l bs. on a l evel

and addi ng t o t hi s

50 per cent , on t he amount of gr avi t y al one, f or t he

i ncr eased power r equi r ed t o r ai se t he hor se i t sel f , t he

whol e f or ce exer t ed wi l l be capabl e of dr awi ng on a

l evel 1 t on 1600 l bs. + 800 = 2 t ons 1601bs. Now, ad-

mi t t i ng t hat i n descendi ng t he pl ane af t er havi ng passed

over t he summi t , t he f or ce of dr aught r equi r ed wi l l be

somet hi ng l ess t han t hat whi ch i s necessar y on a l evel ,

yet t he bal ance i s so deci dedl y i n f avour of a l evel r oad,

t hat no one coul d hesi t at e i n pr onounci ng a deci si on

t o t hat ef f ect .

82

CHAPTER VI I I .

On t he Met hod of Est i mat i ng t he Pr i ces of Ear t h- wor k,

Page 85 of 103

and ot her ki nds of Labour necessar y i n t he I mpr ove-

ment and Repai r of Roads.

The par t i cul ar ci r cumst ances of di f f er ent l ocal i t i es

exer ci se so much i nf l uence on t he val ue of most

descr i pt i ons of l abour and mat er i al s necessar y i n r oad-

maki ng, t hat any t hi ng l i ke a gener al scal e, compr i si ng

al l ki nds of l abour , woul d be ent i r el y out of t he ques -

t i on, and pr obabl y qui t e i nappl i cabl e t o ever y ot her

t han t he par t i cul ar di st r i ct f r om whi ch t he dat a f or i t s

const r uct i on had been der i ved. Thi s r emar k appl i es

t o t he pr i ces of di ggi ng, scr eeni ng, br eaki ng, washi ng,

and ot her wi se pr epar i ng gr avel ; t he pr i ces of quar r y -

i ng and car t i ng st one, and f or mi ng t he pi t chi ng i n t he

bed of t he r oad; al so t o t he pr i ces of f enci ng and

di t chi ng, const r uct i ng dr ai ns, f oot pat hs, &c. Al l t hese

ki nds of l abour var y i n val ue, and t he pr i ce t o be pai d

f or t hem, accor di ng t o t he condi t i on of t he l abour i ng

popul at i on, and t hei r usual empl oyer s t he f ar mer s, and

accor di ng t o ot her ci r cumst ances whi ch i t wi l l not be

necessar y her e t o ent er upon.

I n t he i mpr ovement of r oads upon an ext ensi ve

scal e, however , t he pr ecedi ng ki nds of l abour ar e al l

of mi nor i mpor t ance as compar ed wi t h t hat of exca-

vat i ng ear t h and f i l l i ng" i t i nt o embankment s, i n or der ,

by t hus l ower i ng t he hi l l s and r ai si ng t he val l eys, t o

pr oduce mor e gr adual i ncl i nat i ons, and consequent l y

a bet t er ki nd of r oad. The val ue of t hi s descr i pt i on

of wor k ( al t hough, as may nat ur al l y be supposed, i t

83

f or ms a st udy of t he gr eat est consequence t o al l t hose

engaged i n t he management of r oads, ) i s gener al l y ver y

l i t t l e under st ood ; and many and ser i ous ar e t he evi l s

whi ch have f al l en upon t he heads of t r ust ees and sur -

veyor s f r om t he want of pr act i cal knowl edge on t hi s

subj ect . The obvi ous dat a f r om whi ch t he val ue of

excavat i ng ear t h shoul d be comput ed, consi st of t he

amount or quant i t y of t he mat er i al whi ch can be ex -

cavat ed by a gi ven quant i t y of l abour ; and t hus, i f t he

val ue of t hi s l abour be known, we obt ai n at once t he

pr i ce of t he wor k done, and may est i mat e f r om such

gr oundwor k t he val ue of any ot her quant i t y, gr eat or

smal l .

These dat a of cour se can onl y be der i ved, i n t he

f i r st i nst ance, f r om act ual pr act i cal obser vat i on and

exper i ence on many and di f f er ent wor ks; but bei ng

once known, t hey become of gr eat i mpor t ance i n t he

busi ness of est i mat i ng t he f ut ur e cost of any wor ks of

t he same ki nd.

The wor kmen empl oyed i n ear t h excavat i ons ar e

al ways di vi ded i nt o t wo cl asses, get t er s and f i l l er s ;

t he f or mer empl oyed i n under mi ni ng, dr i vi ng down

by pi l es, and br eaki ng t o pi eces wi t h pi ckaxes t he

ear t h t o be l oaded i nt o t he car t s or bar r ows by t he

f i l l er s. I t wi l l be seen, i n t he cour se of t he f ol l owi ng

obser vat i ons, t hat i n det er mi ni ng t he pr i ce of ear t h-

wor k, i t i s ver y i mpor t ant t o obt ai n an accur at e know-

Page 86 of 103

l edge of t he pr opor t i on i n whi ch t hese t wo cl asses,

get t er s and f i l l er s, ar e r equi r ed t o be empl oyed.

Wher e any consi der abl e quant i t y of ear t h has t o

be r emoved, t he moder n pr act i ce i s t o l ay down i r on

r ai l s f or t he waggons t o t r avel on f r om t he excavat i on

t o t he embankment . I t i s f ound i n such cases t o be

t he i nt er est of t he cont r act or , t hat t he r oads f r om t he

excavat i on t o t he t eami ng- pl aces shoul d be const r uct ed

G 2

84

i n a ver y per f ect manner , and t hat heavy waggons of

t he most dur abl e make shoul d be empl oyed. We may

r eadi l y concei ve t he ext ensi ve est abl i shment of r oads

and waggons necessar y i n some of t he gi gant i c wor ks

of t he gr eat l i nes of r ai l way, on whi ch i t i s by no

means uncommon t o meet wi t h si ngl e hi l l s t o be

l ower ed and f i l l ed i nt o a val l ey cont ai ni ng upwar ds of

a mi l l i on of cubi c yar ds, wi t h a di st ance of car r i age

var yi ng f r om one t o f i ve mi l es. I n t he t r anspor t of

such vast masses of ear t h f or such consi der abl e di s -

t ances, t he r oads cannot be t oo wel l const r uct ed ; and

i n t he end i t wi l l gener al l y be f ound t hat capi t al ex -

pended i n t hi s way pr oduces a ver y sat i sf act or y r et ur n.

A wi de di f l f er ence exi st s, however , bet ween t he vast

ear t h- wor ks of t he r ai l ways and t hose whi ch ar e usual l y

necessar y i n r oad f or mat i ons, wher e t he quant i t y of

ear t h t o be excavat ed f r om any one pl ace sel dom

exceeds f our or f i ve t housand yar ds, and scar cel y ever

amount s t o t went y t housand. I n wor ks of a nat ur e

compar at i vel y so t r i f l i ng, t he expense of heavy waggons,

and t he r ai l s and sl eeper s necessar y t o car r y t hem,

woul d on no account be j ust i f i ed.

I shal l t her ef or e conf i ne mysel f t o t hose met hods of

r emovi ng ear t h whi ch ar e mor e par t i cul ar l y adapt ed

f or smal l quant i t i es and shor t di st ances. Of al l t he

i mpl ement s empl oyed f or t hi s pur pose, t he com mon

ear t h wheel bar r ow i s per haps t he most conveni ent , not

onl y f r om t he ease wi t h whi ch i t can be l oaded, but

f r om t he gr eat f aci l i t y wi t h whi ch i t can be br ought t o

t he ver y spot wher e i t has t o be f i l l ed or empt i ed. By

si mpl y t ur ni ng t he di r ect i on of t he spur r i ng, whi ch i s

gener al l y a 10 or 14 f eet pl ank, wi t hout al t er i ng t he

di r ect i on of t he mai n l i ne of wheel i ng pl anks, t he

bar r ows can be f i l l ed at t he f ace of t he cut t i ng, or

empt i ed at t l i e t eami ng- pl ace at t he pr eci se spot r e-

85

qui r ed. But wi t h waggons and r ai l s t i i e case i s ver y

di f f er ent ; f or any al t er at i on at ei t her end of t he r oad

r equi r es gener al l y a consi der abl e l engt h of r ai l s t o be

t aken up and r epl aced, an oper at i on whi ch i s f ound

ver y t edi ous and t r oubl esome, and whi ch cont r i but es

ver y much t o i ncr ease t he expense of t he t eami ng.

Page 87 of 103

Wher e waggons ar e empl oyed, t hi s par t of t he wor k

sel dom cost s l ess t han I d. per cube yar d; and i n

wi nt er and wet weat her , I have f r equent l y known t he

t eami ng of adhesi ve cl ays, and some descr i pt i ons of

wet sand, t o cost f r om t hr ee- hal f pence t o t wopence per

cube yar d.

The advant age of f i l l i ng i nt o bar r ows i nst ead of

waggons I est i mat e, f r om pr act i cal exper i ence, t o be

equal t o t he r emoval of t he ear t h, af t er f i l l i ng i t , t o a

di st ance of one st age of wheel i ng; or i n ot her wor ds,

t he same set of f i l l er s i n t he same mat er i al wi l l f i l l and

move wi t h bar r ows, t o a di st ance of one st age, f or t he

same pr i ce t hat t hey can f i l l al one i nt o t he waggons.

Thi s ar i ses f r om t he ext r a l i f t t he wor kman must make

t o r ai se hi s l oad over t he si de of t he waggon : and not

onl y i s i t necessar y i n t hi s way t o car r y i t upwar ds a

much gr eat er di st ance, but t he moment t he wor kman

r ai ses hi msel f t o a per pendi cul ar posi t i on, he wor ks t o

gr eat di sadvant age ; f or i t r equi r es much mor e st r engt h

t o r ai se t he same wei ght when he once el evat es hi s

posi t i on, t han whi l st he r emai ned i n a l eani ng or st oop-

i ng at t i t ude. I n t he l at t er posi t i on t he wei ght of hi s

body power f ul l y assi st s i n br i ngi ng up t he l oad, but i n

t he upr i ght post ur e he has not hi ng t o assi st hi m but

hi s ar ms. I n f i l l i ng i nt o a waggon al so, t he const ant

st r ai n upon hi s l oi ns i s so excessi ve, t hat he cannot

t ake up at any one t i me, and deposi t i n one of t he hi gh

waggons, mor e t han t wo- t hi r ds of t he l oad t hat he

coul d r ai se and f i l l wi t h ease i nt o a bar r ow. I t woul d

seem t hat t hese causes ver y sat i sf act or i l y account f or

I I

8G

t he di f f er ence al r eady ment i oned bet ween t he t wo ki nds

of f i l l i ng. The quant i t y of ear t h, however , whi ch t he

bar r ow i s capabl e of hol di ng bei ng ver y smal l , i t i s

obvi ous t hat t hi s mode of r emoval woul d become

t edi ous and expensi ve f or l ong di st ances; and i t i s

f ound accor di ngl y, t hat t he bar r ow cannot be econo-

mi cal l y empl oyed i n t he r emoval of ear t h whi ch has t o

be t aken mor e t han si xt y yar ds f r om t he f ace of t he

cut t i ng. A st age of r unni ng wi t h bar r ows i s t went y

yar ds, and t he pr i ce per st age I d. per yar d : i t i s how-

ever usual f or t he pr i nci pal cont r act or t o bar gai n wi t h

hi s gangsman or f or eman at a pr i ce per yar d, f or any

di st ance not exceedi ng t went y yar ds f r om t he f ace of

t he cut t i ng, and at t he r at e of I d. per yar d ext r a f or

ever y st age of t went y yar ds beyond t he f i r st st age ; t hus

st uf f r equi r i ng one get t er t o t hr ee f i l l er s woul d cost

6d. per yar d. I t must be her e obser ved, t hat one man

can wheel t o t he di st ance of t went y yar ds f or t hr ee

f i l l er s, or f r om f or t y t o f i f t y yar ds per day ; t hus t he

cost of Gd. per yar d i s i ncur r ed, f i l l i ng Sd. , get t i ng I d. ,

wheel i ng t wo ext r a st ages 2d. At t hi s r at e of pay si x

men wi l l r emove about f or t y- t wo yar ds, and ear n f or

t hei r l abour 3s. 6d. per day ; each f i l l er f i l l i ng f our t een

yar ds, and r emovi ng i t f r om t he f ace t o t he di st ance,

Page 88 of 103

as i t i ncr eases, f r om one t o t went y yar ds.

Wi t h r ef er ence t o t he best descr i pt i on of car t or

waggon t o be empl oyed, when i t becomes necessar y t o

abandon t he use of t he bar r ow, t her e ar e of cour se as

many di f l er ent opi ni ons as t her e ar e var i et i es of f or m

and f i gur e i n t he vehi cl es t hemsel ves. I have mysel f

devot ed much at t ent i on t o t hi s subj ect , and havi ng

used many di f f er ent ki nds, am enabl ed t o poi nt out

one or t wo whi ch possess near l y equal advant ages i n

poi nt of conveni ence and economy. One of t he best

wi t h whi ch 1 am acquai nt ed i s t he t hr ee- wheel ed

car t . These can be t aken i n and out of t he cut t i ng.

87

ei t her backwar ds or f or war ds : t hey st and l ow, and

ar e t her ef or e easi l y l oaded, and have a deci ded ad-

vant age over t he common t wo- wheel ed car t , and t he

Scot ch one- hor se cope- car t , on account of t he ease

and expedi t i on wi t h whi ch t hey can be di spat ched f r om

t he f ace of t he cut t i ng and f r om t he t eami ng- pl ace.

A gr eat deal of t i me i s al ways l ost wi t h t he common

t wo- wheel ed car t s, because t he hor se must wai t dur i ng

t he pr ocess of l oadi ng and unl oadi ng; but wi t h t he

t hr ee- wheel ed car t t he hor se dr aws wi t h chai ns, whi ch

ar e hooked on t o t he l oaded waggon, whi ch, on comi ng

t o t he f ace of t he cut t i ng, i s not det ai ned t her e a mo-

ment l onger t han i s occupi ed by t hi s oper at i on : and t he

same t hi ng t akes pl ace at t he t eami ng- head, wher e t he

hor se, as soon as he ar r i ves wi t h a l oaded car t , i s hooked

on t o t he one whi ch he had l ef t t her e t he l ast t r i p, and

r et ur ns as qui ckl y as he can t o t he f ace of t he cut t i ng.

I n t hi s way t he t hr ee- wheel ed car t s wor k r emar kabl y

wel l , and wi t h gr eat r egul ar i t y, par t i cul ar l y i n f i ne

weat her , and good dr y shi f t i ng ear t h. Al t hough i n wet

weat her , and wi t h cl ayey ear t h t o r emove, t hey cannot

be so st r ongl y r ecommended, yet t her e ar e so many

t i mes and pl aces wher e t hese car t s can be empl oyed t o

advant age, t hat t hey ought , i f possi bl e, i n al l ear t h-

wor ks t o be i n r eadi ness f or t he occasi on whi ch may

cal l t hem i nt o use. I n f or mi ng embankment s, wher e

i t i s i mpor t ant t hat r api d consol i dat i on shoul d t ake

pl ace, t he t hr ee- wheel ed car t s ar e ext r emel y val uabl e,

because t hey can be t eamed over a t wo f eet f ace al most

as conveni ent l y as over a heavi er and deeper l i f t ; and

t he embankment may t hus be f or med i n shal l ow l ayer s,

over whi ch t he const ant t r avel l i ng of t he hor ses and

car t s pr oduces t he ef f ect of consol i dat i on, al most si mul -

t aneousl y wi t h t he compl et i on of t he embankment .

Ear t h whi ch has been f i l l ed i n t hi s way i s al so mor e

l i kel y t o st and f i r m, and much l ess l i abl e t o sl i ps t han

88

t hat whi ch has been pl aced i n embankment i n a l ess

compr essed st at e. Thr ee- wheel ed car t s may be econo-

mi cal l y used i n r emovi ng ear t h t o a di st ance of about

Page 89 of 103

hal f a mi l e, or say 900 yar ds; and t he cost of car r i age

may be t aken at about ] d. f or ever y 100 yar ds, wher e

t he di st ance of r emoval i s about 300 yar ds.

I have obser ved t hat a good hor se wi l l make f r om

f or t y- f i ve t o f i f t y j our neys per day, dr awi ng on an

aver age 18 cube f eet at a t i me ; or i n ot her wor ds, a

good hor se wi l l r emove f r om 30 t o 33 cube yar ds per

day t o a di st ance of 300 yar ds f r om t he f ace t o t he

t eami ng, or unl oadi ng end : wher e, however , t he l engt h

of car r i age exceeds t hi s di st ance, and t he l oadi ng

and unl oadi ng become l ess f r equent , t he expense of

car r i age wi l l be pr opor t i onabl y di mi ni shed. I n t he

same r at i o al so t he cost wi l l be augment ed f or shor t er

di st ances t han 300 yar ds, wher e of cour se t he i nt er r up-

t i ons of l oadi ng and unl oadi ng ar e mor e f r equent .

Anot her descr i pt i on of car t whi ch I have ext en-

si vel y empl oyed i n r emovi ng smal l hi l l s, has been f ound

ver y conveni ent bot h f or l oadi ng and t eami ng. Thi s

i s t er med a go- car t , and has somet i mes been r un by

men upon pl anks; but as t hey ar e ver y apt t o get of f

t he t r acks, and dest r oy t he pl anks i n an ext r aor di nar y

manner , I do not r ecommend t hei r use i n t hi s way.

The go- car t has t wo l ong t r ams or shaf t s, t o t he end

of whi ch t he hor se may be hooked, and i s suppor t ed by

t vvo l egs i n f r ont , whi ch pr eser ve t he car t when at r est

i n a hor i zont al posi t i on. When t he car t i s i n mot i on,

t he dr i ver t r avel s bet ween t he shaf t s, hol di ng t hem up

t o cl ear t he l egs f r om t ouchi ng t he gr ound, and pr event

t he car t f r om t i ppi ng over , as i t woul d be l i kel y t o do

wi t h onl y one poi nt of suppor t .

I pr el ' er t hese car t s made l ar ge and ver y st r ong,

wi t h subst ant i al wheel s : t hey wi l l car r y on a good

r oad f r om 18 t o 23 cube f eet of ear t h, and wi t h t hi s

89

l oad t he hor se wi l l t r avel at a f ai r speed. These

car t s possess al l t he r equi si t es of t he t hr ee- wheel ed

ki nd, bot h i n t he f aci l i t y wi t h whi ch t hey can be

l oaded and unl oaded wi t hout det ent i on of t he hor se,

and i n t hei r capabi l i t y of bei ng t eamed i n shal l ow l i f t s.

I n some ot her r espect s t he go- car t s ar e super i or t o t he

f or mer ki nd, par t i cul ar l y on sof t or new made r oads,

wher e t hey can be dr awn wi t h mor e ease t han t he

t hr ee- wheel ed car t , i n whi ch t he t hi r d wheel adds con-

si der abl y t o t he hor se' s dr aught . On t he ot her hand,

t he go- car t s ar e not so easi l y managed as t he t hr ee-

wheel ed cont r i vance, whi ch may ver y saf el y be en-

t r ust ed t o a boy; but t he go- car t r equi r es a man, or

at al l event s a st r ong and act i ve yout h, t o hol d up t he

shaf t s and manage t he hor se, whi ch i s t r avel l i ng bef or e

hi m. Of al l t he car t s I have t r i ed f or t he r emoval of

ear t h t o shor t di st ances, I never f ound any t o equal i n

conveni ence a smal l go- car t of l i ght const r uct i on,

cont r i ved and used by mysel f on t he Uni on Canal , i n

Scot l and. These car t s, of whi ch a dr awi ng and de-

scr i pt i on ar e gi ven i n t he r ecent cel ebr at ed publ i cat i on

by Mr . Weal e, of t he " Engi neer i ng Wor ks of Gr eat

Br i t ai n, " cont ai ned each about 18 cube f eet of ear t h,

Page 90 of 103

and wer e r un by men wi t h gr eat ease on l i ght r ai l s, *

l ai d down on l ongi t udi nal bear i ng pl anks, 10 i nches

wi de, 3 i nches t hi ck, suppor t ed on wooden sl eeper s.

The t ai l - boar d ; s hung by hi nges, and i s di sengaged

and shut agai n by t he man at t he t eami ng- pl ace, wi t h-

* I t may be necessar y t o expl ai n t hat t l i e r ai l s her e ment i oned bor e no

r esembl ance t o t hose used i n r ai l r oads of t he pr esent day. They wer e si mpl y

f l at bar s of i r on, f i xed upon t he bear i ng pl anks by nai l s and st r aps. To

moder n cont r act or s cngag: ed i n l ar ge ear t hwor ks I shoul d r ecommend t he

r ai l adopt ed by Mr . Gi bbs, on t he London and Cr oydon Rai l way, as bei ng

deci dedl y super i or t o ever y ot her wi t h whi ch I am acquai nt ed. Thi s r ai l was

desi gned by Mr . Gi bbs ent i r el y t o di spense wi t h t he use of chai r s, and i s

accor di ngl y f ast ened t o t he l ongi t udi nal bear er s by scr ews passi ng t hr ough t he

br oad base of t he r ai l . Gr eat sol i di t y i s t hus secur ed, and t he r ai l at t he

same t i me possesses t he r ecommendat i on of bei ng l i ght er , and mor e econo-

mi cal t han any ot her hi t her t o adopt ed.

90

out qui t t i ng hi s st at i on at t he shaf t s : t hus not onl y i s

much t i me saved i n t eami ng, but t he expense of i t i s

al so avoi ded.

Havi ng det er mi ned, accor di ng t o t he par t i cul ar

ci r cumst ances of t he case, t he ki nd of waggon or car t

t o be empl oyed i n r emovi ng t he ear t h f r om t he cut t i ngs

t o t he embankment s on t he i nt ended r oad, t he at t en-

t i on of t he engi neer or sur veyor must be di r ect ed t o a

st i l l mor e i mpor t ant par t i n t he busi ness of est i mat i ng;

namel y, t he pr eci se nat ur e of t he ear t h wi t h whi ch t he

wor ks ar e t o be const r uct ed.

I t must be obvi ous, t hat t he gener al name of t he

ear t h, such as cl ay, sand, gr avel , or chal k, af f or ds by

no means a cor r ect cr i t er i on by whi ch t o j udge of i t s

r eal nat ur e ; because al l of t hese, and mor e par t i cul ar l y

t he cl ays, cont ai n amongst t hemsel ves many shades of

di f f er ence i n r espect of har dness and t enaci t y. The

ext ent t o whi ch any par t i cul ar ear t h i s char act er i zed

by one or bot h of t hese qual i t i es, det er mi nes t he nat ur e

of t he mat er i al i n quest i on ; because t hey i ndi cat e t he

ease or t he di f f i cul t y wi t h whi ch t he ear t h can be br oken

up, and ot her wi se separ at ed f r om t he gener al mass, i nt o

pi eces of sui t abl e si ze f or l oadi ng i nt o car t s.

The f acul t y of bei ng abl e t o pr onounce cor r ect l y on

t he nat ur e of t he ear t h t o be r emoved, can onl y be

acqui r ed f r om a l ong cour se of pr act i ce, whi ch shal l

have af f or ded oppor t uni t i es of wi t nessi ng t he execut i on

of ear t h- wor k i n ever y di f f er ent var i et y of ci r cumst ance

and posi t i on. Such a cour se of pr act i ce can al one

f ur ni sh t he or i gi nal dat a al r eady ment i oned, f r om

whi ch t o det er mi ne t he amount of l abour r equi r ed i n

t he r emoval of di f f er ent descr i pt i ons of ear t h. Thi s

of cour se i s t he same t hi ng as t o be abl e accur at el y t o

j udge i t s pr eci se nat ur e, because upon t hi s depends

t he ext ent of l abour necessar y t o pr oduce a cer t ai n

ef f ect . I t i s by no means suf f i ci ent t o det er mi ne t hese

Page 91 of 103

91

dat a, as some have at t empt ed t o do, f r om t he si ngl e

i sol at ed obser vat i on of one pi ece of wor k managed i n

a par t i cul ar manner , whi ch may be j udi ci ous or ot her -

wi se, accor di ng t o ci r cumst ances. Not hi ng i n f act i s

mor e common t han t o see t he execut i on of ear t h- wor k,

under t he management of i gnor ant cont r act or s and

i nexper i enced gangsmen, cost i ng f r om one- t hi r d t o

one- hal f mor e t han i t woul d under pr oper and j udi ci ous

ar r angement s.

Thi s may ar i se f r om t he awkwar dness and i ncom-

pet ency of t he wor kmen, even when wel l pr ovi ded wi t h

i mpl ement s ; and i n many ot her cases, f r om t he i nsuf f i -

ci ent suppl y of wor ki ng i mpl ement s and hor ses, t he

want of good r oads, and ot her r equi si t es of t he same

ki nd. The di f f i cul t i es occasi oned by a nar r ow and

conf i ned syst em of management , adopt ed usual l y under

a f al se i mpr essi on of economy, wi l l i nvar i abl y pr oduce,

i n t he ver y best men, an ef f ' ect so di spi r i t i ng t hat t hey

cannot do mor e t han hal f or t wo- t hi r ds of t he wor k,

whi ch a pr oper syst em of management woul d r ender

t hem capabl e of per f or mi ng.

By means of t he pr act i cal exper i ence t o whi ch I

have al l uded, and whi ch cannot be ot her wi se acqui r ed

t han f r om ext ensi ve obser vat i ons on t he pr ogr ess of

ear t h cut t i ngs, t he st udent wi l l be abl e, on vi ewi ng t he

f ace of an open cut t i ng, t o det er mi ne how many yar ds

per day of t he ear t h, whi ch t he cut t i ng exhi bi t s, a good

wor kman can f i l l i nt o t he vehi cl e i nt ended f or i t s r e-

moval . Fr om t he same exper i ence al so he wi l l be

abl e t o j udge upon anot her poi nt of no l ess i mpor t ance,

namel y, t he ext ent of pr epar at i on whi ch t he ear t h must

under go i n t he way of br eaki ng up, bef or e i t becomes

r eady f or t he f i l l er s. The pr opor t i on of get t er s neces -

sar y t o suppl y and keep const ant l y empl oyed a gi ven

number of f i l l er s bei ng t hus known, t he dat a f or val ui ng

t he pr i ce of any ear t h excavat i on ar e at once i n pos -

92

sessi on of t he engi neer . He may now wi t h conf i dence,

af t er i nspect i ng t he t r i al pi t s and casual openi ngs whi ch

ar e t o be f onnd i n t he nei ghbour hood of most publ i c

wor ks, cl assi f y t he var i ous ki nds of ear t h accor di ng t o

t hei r sever al qual i t i es, and det er mi ne f or each t he

pr i ces on whi ch hi s est i mat es ar e t o be f r amed.

I f we consi der , however , t he ext ent of pr act i cal

exper i ence, and t he var i et y of obser vat i on necessar y t o

qual i f y an engi neer t hus t o j udge of t he val ue of ear t h

excavat i on, we shal l be at no l oss t o account f or t he

et er nal di f f er ence of opi ni on amongst engi neer s i n al l

t hat r el at es t o t he pr i ces of t he wor ks under t hei r con-

t r ol : nor f or t he same r eason i s t her e any t hi ng at al l

sur pr i si ng i n t he const ant r ecur r ence, sessi on af t er ses -

si on, of t he ext r emel y conf l i ct i ng evi dence br ought

bef or e Par l i ament on t he subj ect of est i mat es f or publ i c

wor ks. A gr eat er r or i nt o whi ch st udent s ar e apt t o

f al l when at t empt i ng t o acqui r e f or t hemsel ves a know-

Page 92 of 103

l edge of pr i ces, ar i ses f r om t he supposi t i on t hat t hey

can, by obser vi ng per sonal l y t he pr ogr ess of one or

t wo ear t h- wor ks under t hei r i nspect i on, and by com-

par i ng t he dai l y pr ogr ess wi t h t he quant i t y of l abour

expended i n t he execut i on, ar r i ve at t he r eal cost of

si mi l ar wor ks i n ot her si t uat i ons. Not hi ng can be mor e

er r oneous t han t hi s ; f or such a cour se of obser vat i on

does not even f ur ni sh dat a suf f i ci ent t o det er mi ne t he

cost of t he par t i cul ar wor ks whi ch have been t he sub-

j ect of obser vat i on, much l ess of ot her wor ks whi ch

may be consi der ed anal ogous t o t hose or i gi nal l y ob-

ser ved. I n or der t o expl ai n t hi s, i t must be r emem-

ber ed, t hat t her e ar e many ci r cumst ances i n al l ear t h

excavat i ons whi ch occur t o occasi on expense t o t he

pr i nci pal cont r act or , and wi t h whi ch t he gangsmen have

not hi ng t o do> Thus t hese ci r cumst ances, al t hough

most i mpor t ant as i nf l uenci ng ver y mat er i al l y t he pr i ce

of t he wor k, coul d never be known t o t he most scr ut i -

93

ni zi ng i uspect or or t i i ne- kceper , unl ess i nst r uct ed by t he

cont r act or hi msel f . The execut i on of t he wor k may be

at t ended al so by ot her ci r cumst ances, of whi ch t he

young engi neer may obser ve t he exi st ence wi t hout

bei ng abl e t o est i mat e t hei r ei f Fect on t he pr i ce of t he

wor k. For exampl e : a cont i nuance of unf avour abl e

weat her may occasi on a dr eadf ul i ncr ease of out l ay i n

t he f or mat i on of pr oper r oads t o car r y t he excavat ed

ear t h, i n addi t i on t o ext r aor di nar y wear and t ear of

t he wor ki ng i mpl ement s, and t he dest r uct i on of hor ses,

car t s, and gear of ever y descr i j j t i on. Somet i mes t he

sl i di ng and gi vi ng way of embankment s, and acci dent s

of t he same ki nd i n t he cut t i ngs, and somet i mes t he

necessi t y f or unexpect ed dr ai nage t o keep t he wor k

dr y dur i ng i t s pr ogr ess, wi l l cont r i but e ver y heavi l y t o

i ncr ease t he pr i ce of t he wor k beyond what mi ght

appear t o a casual obser ver t o be t he cost of i t s

execut i on.

One gr and cause, however , I have not yet men-

t i oned, al t hough i t r anks i n i mj j or t ance bef or e al l t he

ot her s, and t hi s i s t he pr act i ce of f or ci ng t he wor ks,

wi t h t he vi ew of compl et i ng t hem wi t hi n l ess t han a

f ai r and r easonabl e t i me f or t hei r per f or mance. Thi s

pr act i ce, whi ch i s not onl y most dest r uct i ve t o a con-

t r act or ' s i nt er est , but mor e conduci ve t han any ot her t o

t he ext r avagant cost of many gr eat publ i c wor ks, i s

not unf r equent l y per si st ed i n dur i ng t he wor st seasons

of t he year , and t hi s t o such an ext ent as t o r ender i t

necessar y t o car r y on t he wor k ni ght and day t hr ough-

out t he year .

I t woul d be no di f f i cul t t ask t o enumer at e many

ot her ci r cumst ances whi ch woul d r ender t he cost of

any par t i cul ar wor k ver y di f f er ent , accor di ng as t hese

happened t o be f avour abl e, or ot her wi se. I t i s pr o-

babl e, however , t hat enough has been al r eady sai d t o

94

Page 93 of 103

show, t hat t he capaci t y of j ust l y appr eci at i ng t he i n-

f l uence of t hese ci r cumst ances i n var yi ng t he pr i ce of

ear t h- wor k, i s conf i ned al most ent i r el y t o t he expe-

r i enced cont r act or , who, dur i ng a l ong- and i nt i mat e

acquai nt ance wi t h t he subj ect , has dr awn hi s exper i -

ence f r om t he act ual pr of i t or l oss he has hi msel f sus -

t ai ned under l i ke ci r cumst ances.

The pr ecedi ng obser vat i ons, on t he di f i i cul t y of cor -

r ect l y est i mat i ng t he pr i ces of ear t h- wor k, ar e by no

means i nt ended t o det er t he unpr act i sed engi neer or

sur veyor f r om at t empt i ng t o f or m an est i mat e of i t s

cost . They ar e si mpl y desi gned t o show t he f al l acy of

assumi ng any f i xed pr i ces as appl i cabl e t o al l wor k of

t he same ki nd i n ever y si t uat i on ; and i f t hey suggest

t o t he younger member s of t he pr of essi on t he necessi t y

of pr oceedi ng on mor e mi nut e and par t i cul ar dat a t han

t hose usual l y t aken, t he i nt ent i on whi ch has gi ven r i se

t o t hem wi l l be f ul l y accompl i shed. Wi t h t hi s expl a-

nat i on, I pr oceed t o t he det ai l s whi ch have been

al r eady al l uded t o, as cal cul at ed t o si mpl i f y t he

gener al busi ness of est i mat i ng ear t h- wor k.

The var i ous st r at a whi ch ar e f ound i n excavat i ons

made f or r oads, r ai l ways, and canal s, may be cl assed

under t he f ol l owi ng heads :

1st . Under handed sof t ear t hs, such as peat , sof t mar l ,

ouze, sand, gr avel , common moul d, and some of t he

sof t er cl ays.

2nd. Gr af t i ng ear t hs, compr i si ng t he f i r st l ayer , or

one dr aw i n dept h of any t enaci ous ear t h ; al so al l cl ays

r equi r i ng t he use of a f oot - i r on t o f or ce t he gr af t i ng

t ool i nt o t he ear t h, whi ch can be mor e r eadi l y di s -

pl aced and f i l l ed i n t hi s way t han by t he met hod of

f al l i ng i t i nt o t he cut t i ng.

3r d. The ear t hs whi ch r equi r e get t i ng, of whi ch ki nd

ar e al l t he har d cl ays, har d gr avel , chal k, common

95

r ocks of ever y descr i pt i on, and i n f act ever y var i et y

of ear t h whi ch cannot be f i l l ed ei t her by t he common

shovel or gr af t hi g t ool al one, but r equi r es, by some

means or ot her , t o be f or ced t o t he bot t om of t he

cut t i ng, and br oken t o pi eces.

I n j udgi ng t he cost of excavat i ng any of t hese ear t hs,

t her e ar e t wo t hi ngs t o be obser ved, namel y, t he quan-

t i t y whi ch can be f i l l ed by a gi ven amount of l abour ,

and t he number of get t er s necessar y t o keep t hat same

amount of l abour i n oper at i on.

The f i r st cl ass of ear t hs descr i bed above, namel y,

t he under handed st uf f , i s f i l l ed i nt o car t s, or t hr own t o

a di st ance by t he wor kman st andi ng on t he l ower l evel

of t he ear t h whi ch he has t o r emove, and t aki ng up

t he mat er i al on hi s t ool wi t hout any ot her exer t i on

t han t hat of r ai si ng each spade or shovel - f ul l , and

Page 94 of 103

ei t her pl aci ng i t i n a car t , or t hr owi ng i t t o a di st ance,

as may be r equi r ed. I t may be assumed t hat a good

wor kman can easi l y f i l l 20 cube yar ds per day of

under handed st uf f ; and 2d. per yar d woul d t her ef or e be

a f ai r and ampl e r emuner at i on t o be pai d t o t he wor k

man al one f or hi s l abour . The cont r act or ' s expense

f or mat er i al s, super i nt endence, and cont i ngenci es, must

be an af t er consi der at i on, and wi l l var y consi der abl y,

accor di ng t o t he quant i t y of wor k t o be execut ed

whet her i t be wet or dr y

t he f aci l i t y of obt ai ni ng

wor kmen, and t he accommodat i on whi ch t he count r y

wi l l af f or d t hem i n t he way of l odgi ng

t he ki nd

of l and and wat er - car r i age by means of whi ch t he

wor ki ng i mpl ement s must be br ought on t he gr ound

accor di ng t o t he season of t he year

and t o many ot her

ci r cumst ances, whi ch must r ender i t ext r emel y f al l a-

ci ous t o name any f i xed sum, ei t her as a per cent age

or ot her char ge, whi ch wi l l i n al l cases be f ound a

r emuner at i ng pr i ce.

90

The second cl ass of ear t h, or t hat t er med gr af t i ng

st uf f , i s r emoved by a man st andi ng above i t , and

f or ci ng hi s t ool ( whi ch t hence der i ves i t s name of

gr af t i ng, or mor e pr oper l y gr aci ng, t ool ) i nt o t he ear t h

by a st amp of hi s f oot , whi ch has t he shoe pr ot ect ed

wi t h a pi ece of wel l t emper ed st eel , f ast ened on wi t h

l eat her st r aps, and cal l ed a f oot - i r on. The i ncr eased

t i me occupi ed i n dr i vi ng t he t ool i nt o t hese gr af t i ng

ear t hs, may be t aken as near l y equal as possi bl e t o

t he addi t i onal l abour of one get t er f or ever y t wo f i l l er s

empl oyed ; or i n ot her wor ds, i t r equi r es t hr ee men i n

gr af t i ng ear t hs t o per f or m t he same wor k as t wo men

i n under handed st uf f : or agai n, t he pr i ce of 3r f . per yar d

on t he f or mer wi l l onl y af f or d t he same wages as 2c?.

on t he l at t er .

The t hi r d cl ass, or get t i ng st uf f , pr esent s gr eat er

var i et y t han can possi bl y be f ound i n t he t wo f or mer

cl asses t oget her . Even t he cl ays al one ar e not mor e

var i ous i n col our t han i n t hei r di f f er ent degr ees of

t enaci t y and sol i di t y. They r ange t hr ough ever y gr ade

of t hese qual i t i es, f r om t he sof t er ki nds, whi ch ar e

usual l y gr af t ed, up t o t he har d bl ue cl ays, whi ch I

have f ound mor e t r oubl esome and expensi ve t o r emove

t han some of t he har dest whi n- st one and gr ani t e r ocks.

These l at t er I woul d r at her encount er t han some of t he

cl ays I have met wi t h i n t he cour se of my pr act i ce i n

ear t h excavat i ons. I t has been bef or e assumed, t hat a

man can easi l y f i l l t went y yar ds of under handed st uf f i n

a day, and i t mi ght appear at f i r st si ght t hat ( i n t he

case of get t i ng ear t hs) af t er t he st uf f has been br oken

i n pi eces by t he get t er s, i t can be f i l l ed wi t h t he

same f aci l i t y as under handed st uf f . Thi s however i s not

t he case ; f or I can af t i r m, wi t h gr eat conf i dence, t hat

men f i l l i ng ear t h, r equi r i ng f or i nst ance t wo get t er s

t o each f i l l er , and equal bot h i n ski l l and st r engt h t o

97

Page 95 of 103

t he same number wor ki ng i n under handed ear t h, wi l l not

f i l l mor e t han hal f t he quant i t y, or about t en yar ds per

man per day. Thi s gr eat di f f er ence i n t he mer e l abour

of f i l l i ng t he t wo ki nds of ear t h, ar i ses i n some degr ee

f r om t he i nconveni ence of wor ki ng i n t he ver y l i mi t ed

space t o whi ch t he f i l l er s ar e necessar i l y conf i ned at

t he f ace of deep cut t i ngs, and t he f r equent r emoval s

whi ch t he men i n t hi s smal l space ar e obl i ged t o make

f r om one par t i cul ar heap of ear t h t o anot her . The

cr owded st at e of t he f i l l i ng f ace i s f ur t her i ncr eased

by t he pi ckmen, each of whom wi l l occupy t he same

space as t wo f i l l er s. A consi der abl e t i me i s l ost by al l

t he f i l l er s pr evi ous t o ever y f al l of ear t h ; f or whi l st t he

pi l es ar e bei ng dr i ven down, i t i s i mpossi bl e f or t he

f i l l er s t o cont i nue at wor k bel ow. The f i l l er s ar e al so

occasi onal l y kept wai t i ng unt i l t he ear t h, af t er i t s f al l ,

i s pi cked t o pi eces r eady f or f i l l i ng. Last l y, t he t r oubl e

of shi f t i ng r oads i s much i ncr eased i n r emovi ng ear t h

whi ch i s t hus br ought down i n f al l s, and f r om t hese

causes combi ned, t he l abour r equi r ed t o r emove a gi ven

quant i t y of get t i ng st uf f i s about doubl e t he l abour

necessar y t o r emove t he same quant i t y of under handed

mat er i al ; and i t i s a cer t ai n f act , t hat t he mor e ex -

pensi ve any descr i pt i on of ear t h may be t o get , i t i s

al ways mor e expensi ve t o f i l l .

I n or der t o br i ng down f al l s of t he get t i ng ear t h,

and pr epar e i t f or t he f i l l er s, t he pr ocess of under mi n-

i ng i s r esor t ed t o. When a l ongi t udi nal hol l ow i n t he

di r ect i on of t he mass t o be br ought down has been

scooped out at t he bot t om of t he cut t i ng by pr oper l y

poi nt ed pi ckaxes, and t he mass has been f ur t her sepa-

r at ed f r om t he gr eat body of t he ear t h by t r ansver se

upr i ght chamber s, whi ch ar e al so ei t her pi cked or dug

out by t he gr af t i ng t ool , a r ow of pi l es, about t hr ee

^eet , or t hr ee f eet and a hal f i n l engt h, and about f i ve

98

i nches di amet er , pr oper l y shod and hooped wi t h i r on, i s

t hen dr i ven down at t he t op of t he mass by a beet l e of

sui t abl e si ze, and by t hese means i t i s soon f or ced t o

t he bot t om of t he cut t i ng.

I f t he ear t h be t ol er abl y br i t t l e and i nadhesi ve, i t i s

somet i mes br oken i nt o sever al pi eces, and r ender ed

l oose by t he vi ol ence of t he f al l . Gr avel , f or i nst ance,

i s ver y easi l y f i l l ed when once i t has been f or ced t o t he

bot t om of t he cut t i ng; but most of t he cl ays must af t er -

war ds be pi cked t o pi eces by pi ckaxes bef or e t hey can

be f i l l ed i nt o t he waggons.

I t wi l l r eadi l y be seen t hat wher e i t r equi r es t hr ee

men t o get and f i l l 10 cube yar ds of ear t h per day, t he

pr i ce of t hei r l abour al one wi l l amount t o I s. per cube

yar d ; and accor di ngl y i t i s by no means an uncommon

case t o f i nd a cont r act or payi ng hi s men t hi s hi gh pr i ce

when he i s so unf or t unat e as t o encount er t hese ki nds

of cl ay. I n t he case we have supposed, wher e t wo

get t er s ar e r equi r ed t o suppl y each f i l l er , i t i s evi dent

t hat t he get t i ng al one wi l l cost doubl e as much as t he

Page 96 of 103

f i l l i ng, and t he separ at e cost of each wi l l appear f r om

t he f ol l owi ng st at ement :

s. d.

One f i l l er r emoves 10 yar ds at 4c?. 3 4

Two get t er s pr epar e 10 yar ds at 8c? 6 8

Pr i ce of get t i ng and f i l l i ng 10 cube yar ds . . 10

whi ch i s equi val ent t o t he pay of t hr ee men at 3s. 4c?.

each.

So much f or t he cost of t he l abour al one ; and wi t h

r espect t o t he cont r act or ' s r emuner at i on, i t must be

obser ved, t hat t hi s ought t o be est i mat ed at a ver y

di f f er ent amount f r om t hat whi ch he woul d f i nd suf f i -

ci ent t o cl ear al l t he char ges of r emovi ng under handed

ear t hs. I n t he l at t er case, hi s f ur ni shi ngs of mat er i al s

need onl y consi st of t he bar r ows and pl anks or car t s

99

f or conveyi ng t he ear t h f r om t he cut t i ng; but i n r e-

movi ng har d st uf f whi ch r equi r es get t i ng, he i s obl i ged

t o pr ovi de pi cks, beet l es, and pi l es, and t o keep t hese

const ant l y shar pened and i n good r epai r . I n addi t i on

t o t hi s, a ver y consi der abl e i ncr ease of wear and t ear

wi l l be occasi oned t o t he waggons, car t s, or bar r ows,

and must of cour se be est i mat ed accor di ngl y.

I n connect i on wi t h t he i ncr eased expense of r e-

movi ng t he har der ki nds of ear t h, i t may not be con-

si der ed i r r el evant t o gl ance at t he gener al ef f ect whi ch

wi l l be pr oduced i n r espect t o t he t i me of execut i ng

any wor k t hat r equi r es much get t i ng, as compar ed wi t h

ot her ki nds of wor k mor e f avour abl e i n t hei r nat ur e.

For i nst ance ; i f a cut t i ng consi st of under handed ear t h

whi ch r equi r es no get t i ng, i t may be assumed t hat f i f t y

men wi l l f i l l 1000 yar ds per day; but i f t he ear t h r e-

qui r e t wo get t er s t o each f i l l er , i t i s evi dent t hat t hi r t y -

t hr ee out of t he f i f t y must be empl oyed i n br i ngi ng

down f al l s, and br eaki ng up t he ear t h f or t he r emai ni ng

sevent een, whi ch number al one wi l l cont i nue t o be

act ual l y engaged i n f i l l i ng. Suppose now t hat a man

can f i l l 10 yar ds dai l y of t hi s ear t h, t he quant i t y ex -

cavat ed by t he whol e f i f t y men wi l l onl y amount t o

170 yar ds, or about one- si xt h of t he quant i t y whi ch

coul d be excavat ed of under handed ear t h. We per -

cei ve t her ef or e t he necessi t y of per f ect l y ascer t ai ni ng

t he nat ur e of any excavat i on bef or e at t empt i ng t o

est i mat e ei t her t he t i me or t he cost of i t s execut i on.

I n assumi ng t hat a wor kman wi l l not be abl e t o f i l l

mor e t han 10 yar ds a day of ear t h whi ch r equi r es

get t i ng, i t must be under st ood t hat t hi s appl i es t o ear t h

of ver y unf avour abl e char act er ; but i f t he ear t h be of

such a qual i t y as t o r equi r e say one get t er t o t wo

f i l l er s, t he l abour of each f i l l er may be aver aged at

H 2

Page 97 of 103

100

13 or 14 yar ds per day, and t he cost of f i l l i ng i n t hi s

case wi l l t her ef or e amount t o about 3r f . per yar d.

Wi t h r espect t o t he pr i ce of t eami ng, t hi s may be

f ai r l y aver aged at I d. per yar d i n est i mat i ng; but t hi s

must be var i ed accor di ng t o t he nat ur e of t he st uf f .

Sand, gr avel , chal k, and cl ay, when dr y, wi l l al ways

t eam wel l ; but any of t hese ear t hs i n a wet st at e wi l l

become cl ammy and adhesi ve t o a degr ee whi ch i n-

cr eases t he t i me, t he t r oubl e, and expense of t eami ng.

We may now pr oceed t o est abl i sh t he gener al r ul e

f or est i mat i ng t he pr i ce of ear t h- wor k, f ounded upon

t he dat a whi ch have been al r eady l ai d down, and whi ch,

f or t he sake of gr eat er cl ear ness, i t may be necessar y

t o r ecapi t ul at e. I n ear t h whi ch r equi r es one get t er t o

t wo f i l l er s, t he wor k done by t he t hr ee men wi l l be

14 X 2 = 28 yar ds. I n ear t h whi ch r equi r es t wo get t er s

t o one f i l l er , t he wor k done by t he t hr ee men wi l l

amount t o 10 yar ds; and t aki ng t he mean of t hese t wo

amount s, we may assume t he wor k of t wo men i n ear t h

r equi r i ng one get t er t o one f i l l er , equi val ent t o 18 yar ds.

Now i t i s evi dent , t hat i n or der t o af f or d t he same wages

t o t he wor kmen i n each of t hese t hr ee cases, t he pr i ce

t o be pai d f or t he wor k must al ways be i nver sel y

pr opor t i onal t o t he amount of t hat wor k. Thus, i f t he

val ue of t hr ee men' s l abour f or one day be t aken at

105. , or 120 pence, we have Vy, - - [ - ( f , and \ - - ^ f or t he

pr i ce i n pence of get t i ng and f i l l i ng t he t hr ee ki nds of

ear t h r espect i vel y whi ch have been descr i bed above.

The pr i ce f or t he wor st of t he t hr ee ki nds, namel y,

t hat whi ch r equi r es one get t er t o t wo f i l l er s, wi l l t her e-

f or e be ^ ' { - Q = 12( L per cube yar d. The pr i ce f or t he

next i n or der , or t hat whi ch r equi r es equal number s of

get t er s and f i l l er s, wi l l be \ - - ^ = Cf pence per cube yar d ;

and t he pr i ce f or t he best of t he t hr ee, or t hat whi ch

101

r equi r es one get t er t o t wo f i l l er s, wi l l be ^ ^ - ^ = 4f pence

per cube yar d. I n gener al t er ms, i f F and G r epr esent

r espect i vel y t he number of f i l l er s and get t er s r equi r ed

t o excavat e any gi ven quant i t y of ear t h, whi ch may be

r epr esent ed by q, and i f p expr ess t he wages of a

si ngl e wor kman f or t he t i me whi ch i s occupi ed i n ex-

cavat i ng t he quant i t y q, t hen we have

-

- = P t he

pr i ce per yar d of excavat i ng t he ear t h i n quest i on.

I n pr oceedi ng t o a br i ef r evi ew of t he ot her descr i p-

t i ons of l abour r equi r ed i n t he const r uct i on of r oads,

t he next i n i mpor t ance f or r oads const r uct ed wi t h a

pi t ched f oundat i on i s pr obabl y t hat connect ed wi t h t he

suppl y of st ones pr oper f or t hi s pur pose. I n any

count r y wher e an open quar r y exi st s f r om whi ch st one,

no mat t er of what qual i t y, i s pr ocur ed f or bui l di ng

Page 98 of 103

pur poses, t her e Avi l l al ways be f ound an abundance of

wast e r ubbl e, or smal l bl ocks of st one, whi ch cannot be

used f or bui l di ngs of any descr i pt i on, and whi ch t her e-

f or e ar e usual l y r emoved i nt o t he bot t om of t he quar r y

as usel ess mat er i al . Thi s ki nd of wast e st one i s per -

f ect l y adapt ed f or pi t chi ng t he f oundat i ons of r oads,

si nce i t i s onl y r equi r ed t hat t he st ones shal l r ange i n

dept h f r om f our t o seven or ei ght i nches f r om t he apex

or hi ghest poi nt t o t he base, and t hat t he base shal l not

exceed about si x i nches i n wi dt h. I n any quar r i es

pr oduci ng st one f or bui l di ng pur poses, i t wi l l sur el y not

be t oo l ow an est i mat e t o assume t hat r ubbl e of t he

ki nd I have descr i bed may be bought on t he gr ound f or

about 3d. per t on, si nce f or any ot her pur pose i t woul d

scar cel y be wor t h t he expense of car t i ng. Beds of

r ock, whi ch may be used f or r oad pi t chi ng, ar e f r e-

quent l y f ound cr oppi ng out t o t he sur f ace of t he gr ound

i n pl aces wher e st one i s abundant . I n such si t uat i ons,

even wher e no r egul ar quar r y has been opened, t he

st one may be got f or about 3r f . or i d. a l oad. I n some

] 02

pl aces wher e t he di f f i cul t i es of pr ocur i ng st one have

been gr eat er , I have pai d f r om 6d. t o I s. a l oad, t hi s

quant i t y bei ng suf f i ci ent t o pi t ch about f i ve super f i ci al

yar ds of r oad. The char ge of I s. per t on f or pi t chi ng

st ones i s deci dedl y hi gh, and ver y much above t he

usual cost f or whi ch t hey may be pr ocur ed. The pr i ce

of l oadi ng and car t i ng t he st one f r om t he quar r i es may

be t aken on an aver age at about I s. per cube yar d per

mi l e. Of cour se, i f t he di st ance of car r i age be shor t ,

and t he r epet i t i on dur i ng t he day of t he l oadi ng and

unl oadi ng be mor e f r equent , t he cost of car r i age wi l l

be somewhat i n excess of t hi s sum ; and on t he con-

t r ar y, a l ong di st ance, est i mat ed accor di ng t o t hi s r at e,

wi l l af f or d t he car r i er t oo much pr of i t . Pr obabl y f or

any di st ance of car r i age bet ween one and t wo mi l es,

t he pr i ce ment i oned above wi l l be f ound a f ai r r emu-

ner at i on, but f or shor t er di st ances t han a mi l e i t wi l l

be f ar f r om a pr of i t abl e bar gai n t o t he car r i er . I n any

est i mat e of car r i age, however , t he si t uat i on of t he quar r y

wi t h r espect t o t he r oad wher e t he st ones ar e t o be

used must be t aken i nt o consi der at i on, because t he

st at e of t he i nt er medi at e r oads on whi ch t he st ones ar e

t o be dr awn i s of gr eat consequence. The pr i ce of I s.

per yar d per mi l e wi l l be f ound r easonabl e i n any

count r y wher e t he r oad l eadi ng f r om t he quar r y i s a

t ol er abl y f ai r count r y r oad, not wi t hst andi ng t he r ut s

may i n some pl aces be none of t he smoot hest , and t he

bot t om none of t he har dest . Wher e unr easonabl e i n-

cl i nat i ons however exi st on t he communi cat i ng r oads,

t he pr i ce wi l l be r at her i nsuf f i ci ent .

The l abour of pi t chi ng t he r oad af t er t he st ones have

been car t ed and l ai d down r eady f or use, i s wor t h about

l ^ d. per super f i ci al yar d. The pr i ce of pr ocur i ng gr avel

f or t he r oad cover i ng, al t hough mat er i al l y af f ect ed by

t he ci r cumst ances whi ch have been al l uded t o at t he

Page 99 of 103

103

begi nni ng of t hi s chapt er , wi l l not f r equent l y exceed

2s. per cube yar d at t he pi t , af t er t he gr avel has been

cl eaned and sor t ed. I have however known i nst ances,

wher e t he gr avel r equi r ed a gr eat deal of pr epar at i on,

i n t he way of br eaki ng, scr eeni ng, and even washi ng,

i n whi ch t he pr i ce of 4s. per yar d has been pai d, and

t hi s i s t he hi ghest pr i ce wi t h whi ch I am acquai nt ed.

Not hi ng l ess t han act ual exami nat i on of t he count r y,

assi st ed by l ocal i nf or mat i on, wi l l enabl e t he sur veyor

t o est i mat e, i n a new count r y, t he exact pr i ce t o be pai d

f or t he gr avel at t he pi t ; but t hi s pr i ce bei ng once

known, t he val ue of t he mat er i al l ai d down on t he r oad

may be t aken at a shi l l i ng per yar d per mi l e of car r i age,

i n addi t i on t o t he pr i ce at t he pi t .

Al l br i ckwor k r equi r ed f or cul ver t s, br i dges, shaf t s,

or r et ai ni ng wal l s, shoul d be pai d f or by measur e ; and

her e t he pr i ce wi l l depend upon t he r at e of wor kmen' s

wages and upon t he f aci l i t i es of obt ai ni ng br i cks, l i me,

and sand. The l owest pr i ce however at whi ch t he br i ck -

wor k necessar y f or r oads shoul d be est i mat ed, i s 11/ . per

r od of st andar d measur e; because, shoul d t he wor k be

under t aken at any l ower pr i ce, t he sur veyor wi l l have

much t r oubl e t o pr event t he i nt r oduct i on ei t her of i nf er i or

mat er i al s or i mpr oper wor kmanshi p. Thi s i s f ar f r om

bei ng t he aver age cost of t he br i ckwor k i n r oad i m-

pr ovement s. I n many i nst ances wher e t he wor k i s not

ver y massi ve, and consi st s of a l ar ge pr opor t i on of

ci r cul ar bui l di ng, and wher e at t he same t i me t he bui l d-

i ng mat er i al s ar e expensi ve, t he pr i ce amount s t o 15?.

a r od, and t he cont r act or even t hen i s somet i mes i n-

di f f er ent l y r emuner at ed. The var i at i on of pr i ce i s of t en

occasi oned ent i r el y by t he di f f er ent ci r cumst ances under

whi ch t he br i cks can be obt ai ned and br ought upon t he

gr ound. For i nst ance ; I have mysel f bought br i cks at

one gui nea per t housand, and at ot her t i mes have pai d

104

as much as t wo gui neas, i n bot h cases excl usi ve of

car r i age. Suppose now t hat t he cheap br i cks may be

obt ai ned cl ose t o t he wor k ; and on t he ot her hand con-

si der a case wher e a l ong di st ance of bad r oad i nt er -

venes bet ween br i ck- ki l ns, wher e an expensi ve ki nd of

br i ck i s suppl i ed, and t he si t e wher e t he bui l di ng i s t o

be const r uct ed : i t i s obvi ous t hat a vast di f f er ence wi l l

be f ound i n t he pr i ces of t he br i ck- wor k, under t hese

di f f er ent ci r cumst ances, whi ch somet i mes occasi on wor k

t o cost mor e t han doubl e t he pr i ce i n a mor e f avour abl e

l ocal i t y.

The bui l di ng pr i ce al one t o be pai d t o t he wor kman

may be t aken on t he aver age at about t wo gui neas per

r od, and t he f ur ni shi ng of l i me and sand at t wo gui neas

mor e. I t may be est i mat ed t hat t he quant i t y of 4500

br i cks wi l l be necessar y t o f i ni sh a r od of br i ckwor k,

and t he pr i ce of t hi s quant i t y at t he ki l ns, t oget her wi t h

t he cost of car r i age at I s. per t on per mi l e, bei ng added

t o t he f our gui neas assumed f or wor kmanshi p, l i me,

and sand, t he pr i ce per r od wi l l be obt ai ned wi t h suf f i -

Page 100 of 103

ci ent accur acy f or t he appr oxi mat e est i mat e ; but of

cour se a per cent age must be added f or t he cont r act or ' s

pr of i t and t he suppl y of mat er i al s.

Longi t udi nal si de dr ai ns, t hr ee f eet deep, wi t h f i ve-

i nch sough and t i l e l ai d i n t he bot t om, aver agi ng f i f t een

i nches wi de, and f i l l ed t o t he t op wi t h cl ean br oken or

boul der st ones, may be est i mat ed at f r om I s. 6d. t o

2s. Gd. per l i neal yar d, accor di ng t o t he f aci l i t i es of

obt ai ni ng t he st ones. Mi t r e dr ai ns wi l l cost f r om 6d.

t o I s. 3r f . per l i neal yar d.

For mi ng a f oot pat h i n t he best manner , si x f eet i n

wi dt h, wi t h a sod f aci ng i n f r ont , wi l l var y i n pr i ce f r om

I s. t o 2s. 6d. per l i neal yar d.

Havi ng now gone t hr ough most of t he wor ks whi ch

t he sur veyor i s usual l y cal l ed on t o cst i nui t c i n car r yi ng

105

i nt o ef f ect t he i mpr ovement of r oads, and made such

pr act i cal obser vat i ons upon t he gener al met hod whi ch

ought t o be f ol l owed i n est i mat i ng wor ks, as wi l l enabl e

t he young sur veyor t o pr onounce wi t h some conf i dence

upon t he cost of any i mpr ovement s he i s about t o

under t ake, I shal l j j r oceed t o l ay down a f or m of

est i mat e whi ch wi l l ser ve, i n some measur e, t o i l l us-

t r at e t he use of t he pr ecedi ng obser vat i ons.

The r oad f or whi ch t he f ol l owi ng est i mat e has been

f or med we shal l suppose t o be t hi r t y f eet ^ wl de, t o be

equal l y wel l const r uct ed wi t h any par t of t he London

and Hol yhead r oad, t o have a f oot pat h si x f eet mde

on t he nor t h si de, and t o be def i ned on t he sout h si de

by a ver ge, or r ai sed r i dge, el evat ed f r om t he wat er

t abl e up t o t he hei ght of t he cent r e of t he r oad ; t he

f oot pat h and ver ge t o have a sod neat l y and f i r ml y

l ai d on t hei r f r ont f aci ng. We shal l suppose t he ext ent

of r oad t o be i mpr oved, or newl y const r uct ed, t o be one

mi l e i n l engt h, and t he ear t h- wor k t o consi st of 20, 000

yar ds of cut t i ng of t he f ol l owi ng ki nds :

2000 yar ds of

gr af t i ng st uf f , t o be wheel ed t wo st ages of 20 yar ds

each; 5000 yar ds of get t i ng st uf f , t o be r emoved t wo

st ages of 80 yar ds each, and r equi r i ng one get t er t o

t hr ee f i l l er s ; 5000 yar ds of t he same st uf f " , t o be r emoved

by go- car t s 3 st ages, or 240 yar ds; t he r emai ni ng 8000

yar ds bei ng bad st uf f , t o go 4 st ages by go car t s, and

r equi r es t wo get t er s t o each f i l l er .

Pr obabl e Est i mat e of t he Cost .

Ear t hwor k.

Gr af t i ng ear t h wi l l cost per yar d f or f i l l i ng . . . Sd.

s. d

Wheel i ng by bar r ows t wo st ages 2

Cont r act or ' s mat er i al , pr of i t , &c 1

2000 at ed. 50

Page 101 of 103

Car r i ed f or war d 50

106

s. d

Br ought f or war d 50

Get t i ng st uf f r equi r i ng one get t er t o t hr ee f i l l er s, t o

be r emoved by go- car t s t wo st ages, or 160 yar ds,

wi l l cost f i l l i ng ocL, r emovi ng 2d. , get t i ng \ d. ,

t eami ng \ d. ; cont r act or f or shar peni ng pi cks,

f ur ni shi ng beet l es, &c. i d. , f ur ni shi ng car t s and

l i ght r ai l s \ \ d. ; i n al l 9c?. per yar d.

6000 yar ds at 9r f . 187 10

Get t i ng st uf f al so r equi r i ng one get t er t o t hr ee f i l l er s,

t o be r un by car t s t hr ee st ages, wi l l cost f i l l i ng as

bef or e M. , r emovi ng Sc?. , get t i ng \ d. , t eami ng \ d. ;

cont r act or as bef or e f or f ur ni shi ngs 2d. ; i n al l \ Qd.

per yar d.

6000 yar ds at \ Qd. 208 6 8

Har d get t i ng cl ay r equi r i ng t wo get t er s t o each f i l l er ,

and of whi ch each f i l l er can onl y f i l l 10 yar ds per

day, wi l l cost f or f i l l i ng 4^ . , get t i ng Sr / . , f ur ni shi ng

pi cks, pi l es, beet l es, &c. \ i d. , f ur ni shi ng go- car t s

and r ai l s dd. , car r i age f our st ages Ad. , t eami ng \ d. ;

i n al l 1. 9. di d. per yar d.

8000 yar ds at 1* . 9l d. 716 13 4

Road Pi t chi ng.

Fur ni shi ng t he st ones whi ch cost i n t he quar r y 4d.

per t on, and t o be car t ed a di st ance of t wo mi l es,

at 1* . per t on per mi l e, maki ng i n al l 2, ?. 4d. per

mi l e ; t hen i f one t on wi l l compl et e 3

super f i ci al

yar ds of pi t chi ng si x i nches deep, t he quant i t y

, c . , . , ,

, I ' ^ f ' O X 10

r equi r ed f or one mi l e i n l engt h wi l l be

^ - ^

= 5029 t ons, at 2* . 4r f " ! . . 586 14 4

Labour of pi t chi ng or e mi l e i n l engt h, at Md. per

super f i ci al yar d, or 17, 600 yar ds at \ i d. 9113 4

Foot pat h and Ver ge.

For mi ng and compl et i ng f oot pat h one mi l e i n l engt h,

or 1/ 60 yar ds, at 1 . 9 ?. 164

For mi ng ver ge on t he opposi t e si de of t he r oad,

ei ght een i nches wi de and ni ne i nches hi gh.

1 760 l i neal yar ds at 4d. 29 6 8

Page 102 of 103

Dr ai nage.

A l ongi t udi nal si de dr ai n on each si de of t he r oad,

t hr ee f eet deep, and f i l l ed wi t h cl ean st ones br oken

Car r i ed f or war d 2024 4 4

107

s. d

Br ought f or war d 2024 4 4

t o t he pr oper si ze, i ncl udi ng a f i ve- i nch sough and

t i l e channel t o be l ai d i n t he bot t om.

3520 l i neal yar ds at 1* . 6r f . 264

Mi t r e dr ai ns at i nt er val s of 40 yar ds, each dr ai n

bei ng 12 yar ds l ong, wi l l cost , at I s. per yar d, 12* .

44 dr ai ns at V2s. each 26 8

Road Cover i ng.

Gr avel t o be l ai d down si x i nches i n dept h, a t on of

whi ch wi l l cover about 4 super f i ci al yar ds of t he

r oad, hence a mi l e i n l engt h wi l l r equi r e 4400 t ons ;

t hen t hi s wi l l cost at t he quar r y 2s. 6d. per t on,

car r i age t wo mi l es 2 . , spr eadi ng on t he r oad 6r f . ;

i n al l 5s. per t on.

. 4400 t ons at 5s. 1100

Br i ck- wor k.

I n t hi s mi l e of r oad i t i s necessar y t o bui l d t wo cul -

ver t s, and ot her br i ck- wor k i s i nt r oduced; al t o-

get her 24 r ods of wor k, at 12/ . 10s 300

Cont r act or ' s pr of i t f or super i nt endence, unf or eseen

ci r cumst ances i n t he wor k, and ever y possi bl e

cont i ngency, at 20 per cent 742

3714 12 4

18 6

56 4457 10 10

I beg t o obser ve, wi t h r ef er ence t o t he pr ecedi ng

est i mat e, t hat al t hough on many l ong l i nes of r oad t he

quant i t i es of cut t i ng and embanki ng, at par t i cul ar par t s,

f ar exceed t he amount I have assumed of 20, 000 yar ds

per mi l e, on t he ot her hand i t must be r emember ed,

Page 103 of 103

t hat i n many di st r i ct s t he quant i t y of cut t i ng wi l l not

be f ound near l y so gr eat on an aver age of many mi l es

of r oad communi cat i on. Agai n, t he pr i ces whi ch have

been assumed ar e of cour se hypot het i cal ; but of one

t hi ng I am cer t ai n, t hat 1 have not f al l en i nt o t he er r or

whi ch so many hundr eds have commi t t ed, of under -

r at i ng t he cost of wor ks t o be car r i ed i nt o execut i on.

I bel i eve t hat i n sr ener al t he mat er i al s can be obt ai ned

108

f or l ess t han I have est i mat ed; and t hr oughout t he

l ot of my st at ement s, ! have ear ef ul . y guar dedagams

: hr L. er \ r m. , eadm.

; t : t r 7: : t hf st e : r p^ ^ ng Mmse. t o Ms

r ; " . . t he p- - - ; - r er t t ; r

^ t i M^ W i nt ent i ons ear ned i nt o et i eci l ui

Ud be or e t hem, or t he eont r aet or seeki ng t o der . ve a

eason b e r emnner at i on f or exeeut i ng t he^ or ks- t o

I n and each I woul d say, t hat t hey may saf el y depend

upon t he f ai r ness and candour of t he st at ement s I have

ZZ si nce t hese ar e t he r esul t of a l ong cour se of

Tnl n pr acHce and exper i ence, dur i ng whi ch I have

best owed unwear i ed at t ent i on upon t he met hods f

est i mat i ng engi neer i ng wor ks under ever y possi bl e

var i et y.