the life of thomas telford-第54节

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being　also　killed。〃*＇2＇　　The　remaining　part　of　the　bridge　continued

for　some　time　unrepaired；　just　space　enough　being　left　for　a　single

carriage　to　pass。　　The　road　trustees　seemed　to　be　helpless；　and　did

nothing；　a　local　subscription　was　tried　and　failed；　the　district

passed　through　being　very　poor；　but　as　the　road　was　absolutely

required　for　more　than　merely　local　purposes；　it　was　eventually

determined　to　undertake　its　reconstruction　as　a　work　of　national

importance；　and　50；000L。　was　granted　by　Parliament　with　this

object；　under　the　provisions　of　the　Act　passed　in　1816。　　The　works

were　placed　under　Mr。　Telford's　charge；　and　an　admirable　road　was

very　shortly　under　construction　between　Carlisle　and　Glasgow。

That　part　of　it　between　Hamilton　and　Glasgow；　eleven　miles　in　length；

was　however　left　in　the　hands　of　local　trustees；　as　was　the

diversion　of　thirteen　miles　at　the　boundary　of　the　counties　of

Lanark　and　Dumfries；　for　which　a　previous　Act　had　been　obtained。

The　length　of　new　line　constructed　by　Mr。　Telford　was　sixty…nine

miles；　and　it　was　probably　the　finest　piece　of　road　which　up　to

that　time　had　been　made。



His　ordinary　method　of　road…making　in　the　Highlands　was；　first　to

level　and　drain；　then；　like　the　Romans；　to　lay　a　solid　pavement　of

large　stones；　the　round　or　broad　end　downwards；　as　close　as　they

could　be　set。　　The　points　of　the　latter　were　then　broken　off；　and　a

layer　of　stones　broken　to　about　the　size　of　walnuts；　was　laid　upon

them；　and　over　all　a　little　gravel　if　at　hand。　　A　road　thus　formed

soon　became　bound　together；　and　for　ordinary　purposes　was　very

durable。



But　where　the　traffic；　as　in　the　case　of　the　Carlisle　and　Glasgow

road；　was　expected　to　be　very　heavy；　Telford　took　much　greater

pains。　　Here　he　paid　especial　attention　to　two　points：　first；　to　lay

it　out　as　nearly　as　possible　upon　a　level；　so　as　to　reduce　the

draught　to　horses　dragging　heavy　vehicles；one　in　thirty　being

about　the　severest　gradient　at　any　part　of　the　road。　　The　next　point

was　to　make　the　working；　or　middle　portion　of　the　road；　as　firm　and

substantial　as　possible；　so　as　to　bear；　without　shrinking；　the

heaviest　weight　likely　to　be　brought　over　it。　　With　this　object　he

specified　that　the　metal　bed　was　to　be　formed　in　two　layers；　rising

about　four　inches　towards　the　centre　the　bottom　course　being　of

stones　（whinstone；　limestone；　or　hard　freestone）；　seven　inches　in

depth。　　These　were　to　be　carefully　set　by　hand；　with　the　broadest

ends　downwards；　all　crossbonded　or　jointed；　no　stone　being　more

than　three　inches　wide　on　the　top。　　The　spaces　between　them　were

then　to　be　filled　up　with　smaller　stones；　packed　by　hand；　so　as　to

bring　the　whole　to　an　even　and　firm　surface。　　Over　this　a　top　course

was　to　be　laid；　seven　inches　in　depth；　consisting　of　properly

broken　hard　whinstones；　none　exceeding　six　ounces　in　weight；　and

each　to　be　able　to　pass　through　a　circular　ring；　two　inches　and　a

half　in　diameter；　a　binding　of　gravel；　about　an　inch　in　thickness；

being　placed　over　all。　　A　drain　crossed　under　the　bed　of　the　bottom

layer　to　the　outside　ditch　in　every　hundred　yards。　　The　result　was

an　admirably　easy；　firm；　and　dry　road；　capable　of　being　travelled

upon　in　all　weathers；　and　standing　in　comparatively　small　need　of

repairs。



A　similar　practice　was　introduced　in　England　about　the　same　time　by

Mr。　Macadam；　and；　though　his　method　was　not　so　thorough　as　that　of

Telford；　it　was　usefully　employed　on　most　of　the　high　roads

throughout　the　kingdom。　　Mr。　Macadam's　notice　was　first　called　to

the　subject　while　acting　as　one　of　the　trustees　of　a　road　in

Ayrshire。　　Afterwards；　while　employed　as　Government　agent　for

victualling　the　navy　in　the　western　parts　of　England；　he　continued

the　study　of　road…making；　keeping　in　view　the　essential　conditions

of　a　compact　and　durable　substance　and　a　smooth　surface。　　At　that

time　the　attention　of　the　Legislature　was　not　so　much　directed　to

the　proper　making　and　mending　of　the　roads；　as　to　suiting　the

vehicles　to　them　such　as　they　were；　and　they　legislated　backwards

and　forwards　for　nearly　half　a　century　as　to　the　breadth　of　wheels。

Macadam　was；　on　the　other　hand；　of　opinion　that　the　main　point　was

to　attend　to　the　nature　of　the　roads　on　which　the　vehicles　were　to

travel。　　Most　roads　were　then　made　with　gravel；　or　flints　tumbled

upon　them　in　their　natural　state；　and　so　rounded　that　they　had　no

points　of　contact；　and　rarely　became　consolidated。　　When　a　heavy

vehicle　of　any　sort　passed　over　them；　their　loose　structure

presented　no　resistance；　the　material　was　thus　completely

disturbed；　and　they　often　became　almost　impassable。　　Macadam's

practice　was　this：　to　break　the　stones　into　angular　fragments；　so

that　a　bed　several　inches　in　depth　should　be　formed；　the　material

best　adapted　for　the　purpose　being　fragments　of　granite；

greenstone；　or　basalt；　to　watch　the　repairs　of　the　road　carefully

during　the　process　of　consolidation；　filling　up　the　inequalities

caused　by　the　traffic　passing　over　it；　until　a　hard　and　level

surface　had　been　obtained。　　Thus　made；　the　road　would　last　for

years　without　further　attention。　　in　1815　Mr。　Macadam　devoted

himself　with　great　enthusiasm　to　road…making　as　a　profession；　and

being　appointed　surveyor…general　of　the　Bristol　roads；　he　had　full

opportunities　of　exemplifying　his　system。　　It　proved　so　successful

that　the　example　set　by　him　was　quickly　followed　over　the　entire

kingdom。　　Even　the　streets　of　many　large　towns　were　Macadamised。

In　carrying　out　his　improvements；　however；　Mr。　Macadam　spent　several

thousand　pounds　of　his　own　money；　and　in　1825；　having　proved　this

expenditure　before　a　Committee　of　the　House　of　Commons；　the　amount

was　reimbursed　to　him；　together　with　an　honorary　tribute　of　two

thousand　pounds。　　Mr。　Macadam　died　poor；　but；　as　he　himself　said；

〃a　least　an　honest　man。〃　　By　his　indefatigable　exertions　and　his

success　as　a　road…maker；　by　greatly　saving　animal　labour；

facilitating　commercial　intercourse；　and　rendering　travelling　easy

and　expeditious；　he　entitled　himself　to　the　reputation　of　a　public

benefactor。



＇Image＇　J。　L。　Macadam。



Owing　to　the　mountainous　nature　of　the　country　through　which

Telford's　Carlisle　and　Glasgow　road　passes；　the　bridges　are

unusually　numerous　and　of　large　dimensions。　　Thus；　the　Fiddler's

Burn　Bridge　is　of　three　arches；　one　of　150　and　two　of　105　feet　span

each。　　There　are　fourteen　other　bridges；　presenting　from　one　to

three　arches；　of　from　20　to　90　feet　span。　　But　the　most　picturesque

and　remarkable　bridge　constructed　by　Telford　in　that　district　was

upon　another　line　of　road　subsequently　carried　out　by　him；　in　the

upper　part　of　the　county　of　Lanark；　and　crossing　the　main　line　of

the　Carlisle　and　Glasgow　road　almost　at　right　angles。　　Its　northern

and　eastern　part　formed　a　direct　line　of　communication　between　the

great　cattle　markets　of　Falkirk；　Crief；　and　Doune；　and　Carlisle　and

the　West　of　England。　　It　was　carried　over　deep　ravines　by　several

lofty　bridges；　the　most　formidable　of　which　was　that　across　the

Mouse　Water　at　Cartland　Crags；　about　a　mile　to　the　west　of　Lanark。

The　stream　here　flows　through　a　deep　rocky　chasm；　the　sides　of

which　are　in　some　places　about　four　hundred　feet　high。　　At　a　point

where　the　height　of　the　rocks　is　considerably　less；　but　still　most

formidable；　Telford　spanned　the　ravine　with　the　beautiful　bridge

represented　in　the　engraving　facing　this　page；　its　parapet　being

129　feet　above　the　surface　of　the　water　beneath。



＇Image＇　Cartland　Crags　Bridge。



The　reconstruction　of　the　western　road　from　Carlisle　to　Glasgow；

which　Telford　had　thus　satisfactorily　carried　out；　shortly　led　to

similar　demands　from　the　population　on　the　eastern　side　of　the

kingdom。　　The　spirit　of　road　reform　was　now　fairly　on　foot。

Fast　coaches　and　wheel…carriages　of　all　kinds　had　become　greatly

improved；　so　that　the　usual　rate　of　travelling　had　advanced　from

five　or　six　to　nine　or　ten　miles　an　hour。　　The　desire　for　the　rapid

communication　of　political　and　commercial　intelligence　was　found　to

increase　with　the　facilities　for　supplying　it；　and；　urged　by　the

public　wants；　the　Post…Office　authorities　were　stimulated　to

unusual　efforts　in　this　direction。　　Numerous　surveys　were　made　and

roads　laid　out；　so　as　to　improve　the　main　line　of　communication

between　London　and　Edinburgh　and　the　intermediate　towns。　　The　first

part　of　this　road　taken　in　hand　was　the　worstthat　lying　to　the

north　of　Catterick　Bridge；　in　Yorkshire。　　A　new　line　was　surveyed　by

West　Auckland　to　Hexham；　passing　over　Garter　Fell　to　Jedburgh；　and

thence　to　Edinburgh；　but　was　rejected　as　too　crooked　and　uneven。

Another　was　tried　by　Aldstone　Moor　and　Bewcastle；　and　rejected　for

the　same　reason。　　The　third　line　proposed　was　eventually　adopted　as

the　best；　passing　from　Morpeth；　by　Wooler　and　Coldstream；

to　Edinburgh；　saving　rather　more　than　fourteen　miles　between　the

two　points；　and　securing　a　line　o