the life of thomas telford-第30章

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which　Telford　was　appointed　engineer　to　the　Ellesmere　Canal　and　the

designing　of　these　gigantic　works。　　He　had　in　the　meantime　been

carefully　gathering　experience　from　a　variety　of　similar

undertakings　on　which　he　was　employed；　and　bringing　his

observations　of　the　strength　of　materials　and　the　different　forms

of　construction　to　bear　upon　the　plans　under　his　consideration　for

the　great　aqueducts　of　Chirk　and　Pont…Cysylltau。　　In　1795　he　was

appointed　engineer　to　the　Shrewsbury　Canal；　which　extends　from　that

town　to　the　collieries　and　ironworks　in　the　neighbourhood　of

Wrekin；　crossing　the　rivers　Roden　and　Tern；　and　Ketley　Brook；　after

which　it　joins　the　Dorrington　and　Shropshire　Canals。　　Writing　to　his

Eskdale　friend；　Telford　said　：　〃Although　this　canal　is　only

eighteen　miles　long；　yet　there　are　many　important　works　in　its

courseseveral　locks；　a　tunnel　about　half　a　mile　long；　and　two

aqueducts。　　For　the　most　considerable　of　these　last；　I　have　just

recommended　an　aqueduct　of　iron。　　It　has　been　approved；　and　will　be

executed　under　my　direction；　upon　a　principle　entirely　new；　and

which　I　am　endeavouring　to　establish　with　regard　to　the　application

of　iron。〃*＇4＇



It　was　the　same　principle　which　he　applied　to　the　great　aqueducts

of　the　Ellesmere　Canal　now　under　consideration。　　He　had　a　model　made

of　part　of　the　proposed　aqueduct　for　Pont…Cysylltau；　showing　the

piers；　ribs；　towing…path；　and　side　railing；　with　a　cast　iron　trough

for　the　canal。　　The　model　being　approved；　the　design　was　completed；

the　ironwork　was　ordered　for　the　summit；　and　the　masonry　of　the

piers　then　proceeded。　　The　foundation…stone　was　laid　on　the　25th

July；　1795；　by　Richard　Myddelton；　Esq。；　of　Chirk　Castle；　M。P。；　and

the　work　was　not　finished　until　the　year　1803；thus　occupying　a

period　of　nearly　eight　years　in　construction。



The　aqueduct　is　approached　on　the　south　side　by　an　embankment　1500

feet　in　length；　extending　from　the　level　of　the　water…way　in　the

canal　until　its　perpendicular　height　at　the　〃tip〃　is　97　feet；

thence　it　is　carried　to　the　opposite　side　of　the　valley；　over　the

river　Dee；　upon　piers　supporting　nineteen　arches；　extending　to　the

length　of　1007　feet。　　The　height　of　the　piers　above　low　water　in　the

river　is　121　feet。　　The　lower　part　of　each　was　built　solid　for　70

feet；　all　above　being　hollow；　for　the　purpose　of　saving　masonry　as

well　as　ensuring　good　workmanship。　　The　outer　walls　of　the　hollow

portion　are　only　two　feet　thick；　with　cross　inner　walls。　　As　each

stone　was　exposed　to　inspection；　and　as　both　Telford　and　his

confidential　foreman；　Matthew　Davidson；*＇5＇　kept　a　vigilant　eye

upon　the　work；　scamping　was　rendered　impossible；　and　a　first…rate

piece　of　masonry　was　the　result。



＇Image＇　Pont…Cyslltau　Aqueduct



Upon　the　top　of　the　masonry　was　set　the　cast　iron　trough　for　the

canal；　with　its　towing…path　and　side…rails；　all　accurately　fitted

and　bolted　together；　forming　a　completely　water…tight　canal；　with　a

water…way　of　11　feet　10　inches；　of　which　the　towing…path；　standing

upon　iron　pillars　rising　from　the　bed　of　the　canal；　occupied　4　feet

8　inches；　leaving　a　space　of　7　feet　2　inches　for　the　boat。*＇6＇

The　whole　cost　of　this　part　of　the　canal　was　47；018L。；　which　was

considered　by　Telford　a　moderate　sum　compared　with　what　it　must

have　cost　if　executed　after　the　ordinary　manner。　　The　aqueduct　was

formally　opened　for　traffic　in　1805。　　〃And　thus；〃　said　Telford；　〃has

been　added　a　striking　feature　to　the　beautiful　vale　of　Llangollen；

where　formerly　was　the　fastness　of　Owen　Glendower；　but　which；　now

cleared　of　its　entangled　woods；　contains　a　useful　line　of

intercourse　between　England　and　Ireland；　and　the　water　drawn　from

the　once　sacred　Devon　furnishes　the　means　of　distributing

prosperity　over　the　adjacent　land　of　the　Saxons。〃



＇Image＇　Section　of　Top　of　Pont…Cyslltau　Aqueduct。



It　is　scarcely　necessary　to　refer　to　the　other　works　upon　this

canal；　some　of　which　were　of　considerable　magnitude；　though　they

may　now　seem　dwarfed　by　comparison　with　the　works　of　recent

engineers；　Thus；　there　were　two　difficult　tunnels　cut　through　hard

rock；　under　the　rugged　ground　which　separates　the　valleys　of　the

Dee　and　the　Ceriog。　　One　of　these　is　500　and　the　other　200　yards　in

length。　　To　ensure　a　supply　of　water　for　the　summit　of　the　canal；

the　lake　called　Bala　Pool　was　dammed　up　by　a　regulating　weir；　and

by　its　means　the　water　was　drawn　off　at　Llandisilio　when　required

for　the　purposes　of　the　navigation；　the　navigable　feeder　being　six

miles　long；　carried　along　the　bank　of　the　Llangollen　valley。

All　these　works　were　skilfully　executed；　and　when　the　undertaking

was　finished；　Mr。　Telford　may　be　said　to　have　fairly　established

his　reputation　as　an　engineer　of　first　rate　ability。



We　now　return　to　Telford's　personal　history　during　this　important

period　of　his　career。　　He　had　long　promised　himself　a　visit　to　his

dear　Eskdale；　and　the　many　friends　he　had　left　there；　but　more

especially　to　see　his　infirm　mother；　who　had　descended　far　into　the

vale　of　years；　and　longed　to　see　her　son　once　more　before　she　died。

He　had　taken　constant　care　that　she　should　want　for　nothing。

She　formed　the　burden　of　many　of　his　letters　to　Andrew　Little。

〃Your　kindness　in　visiting　and　paying　so　much　attention　to　her；〃

said　he；　〃is　doing　me　the　greatest　favour　which　you　could　possibly

confer　upon　me。〃　　He　sent　his　friend　frequent　sums　of　money；　which

he　requested　him　to　lay　out　in　providing　sundry　little　comforts　for

his　mother；　who　seems　to　have　carried　her　spirit　of　independence　so

far　as　to　have　expressed　reluctance　to　accept　money　even　from　her

own　son。　　〃I　must　request；〃　said　he；　〃that　you　will　purchase　and

send　up　what　things　may　be　likely　to　be　wanted；　either　for　her　or

the　person　who　may　be　with　her；　as　her　habits　of　economy　will

prevent　her　from　getting　plenty　of　everything；　especially　as　she

thinks　that　I　have　to　pay　for　it；　which　really　hurts　me　more　than

anything　else。〃*＇7＇　　Though　anxious　to　pay　his　intended　visit；　he

was　so　occupied　with　one　urgent　matter　of　business　and　another　that

he　feared　it　would　be　November　before　he　could　set　out。　　He　had　to

prepare　a　general　statement　as　to　the　navigation　affairs　for　a

meeting　of　the　committee；　he　must　attend　the　approaching　Salop

quarter　sessions；　and　after　that　a　general　meeting　of　the　Canal

Company；　so　that　his　visit　must　be　postponed　for　yet　another　month。

〃Indeed；〃　said　he；　〃I　am　rather　distressed　at　the　thoughts　of

running　down　to　see　a　kind　parent　in　the　last　stage　of　decay；　on

whom　I　can　only　bestow　an　affectionate　look；　and　then　leave　her：

her　mind　will　not　be　much　consoled　by　this　parting；　and　the

impression　left　upon　mine　will　be　more　lasting；　than　pleasant。〃*＇8＇



He　did；　however；　contrive　to　run　down　to　Eskdale　in　the　following

November。　　His　mother　was　alive；　but　that　was　all。　　After　doing　what

he　could　for　her　comfort；　and　providing　that　all　her　little　wants

were　properly　attended　to；　he　hastened　back　to　his　responsible

duties　in　connection　with　the　Ellesmere　Canal。　　When　at　Langholm；

he　called　upon　his　former　friends　to　recount　with　them　the　incidents

of　their　youth。　　He　was　declared　to　be　the　same　〃canty〃　fellow　as

ever；　and；　though　he　had　risen　greatly　in　the　world；　he　was　〃not　a

bit　set　up。〃　　He　found　one　of　his　old　fellow　workmen；　Frank　Beattie；

become　the　principal　innkeeper　of　the　place。　　〃What　have　you　made　of

your　mell　and　chisels？〃　asked　Telford。　　〃Oh！〃　replied　Beattie；

〃they　are　all　dispersedperhaps　lost。〃　　〃I　have　taken　better　care

of　mine；〃　said　Telford；　〃I　have　them　all　locked　up　in　a　room　at

Shrewsbury；　as　well　as　my　old　working　clothes　and　leather　apron：

you　know　one　can　never　tell　what　may　happen。〃



He　was　surprised；　as　most　people　are　who　visit　the　scenes　of　their

youth　after　a　long　absence；　to　see　into　what　small　dimensions

Langholm　had　shrunk。　　That　High　Street；　which　before　had　seemed　so

big；　and　that　frowning　gaol　and　court…house　in　the　Market　Place；

were　now　comparatively　paltry　to　eyes　that　had　been　familiar　with

Shrewsbury；　Portsmouth；　and　London。　　But　he　was　charmed；　as　ever；

with　the　sight　of　the　heather　hills　and　the　narrow　winding　valley



　　　〃Where　deep　and　low　the　hamlets　lie

　　　　Beneath　their　little　patch　of　sky；

　　　　And　little　lot　of　stars。〃



On　his　return　southward；　he　was　again　delighted　by　the　sight　of　old

Gilnockie　Castle　and　the　surrounding　scenery。　　As　he　afterwards

wrote　to　his　friend　Little；　〃Broomholm　was　in　all　his　glory。〃

Probably　one　of　the　results　of　this　visit　was　the　revision　of　the

poem　of　'Eskdale；'　which　he　undertook　in　the　course　of　the

following　spring；　putting　in　some　fresh　touches　and　adding　many　new

lines；　whereby　the　effect　of　the　whole　was　considerably　improved。

He　had　the　poem　printed　privately；　merely　for　distribution　amongst

friends；　being　careful；〃　as　he　said；　that　〃no　copies　should　be

smuggled　and　sold。〃



Later　in　the　year　we　find　him；　on　his　way　to　London　on　business；

sparing　a　day　or　two　for　the　purpose　of　visiting　the　Duke　of

Buckingham's　palace　and　treasures　of　art　at　Stowe；　afterwards

writing　out　an　eight…page　description　of　it　for　the　perusal　of　his

friends　at　Langholm。　　At　another　time；　when　engaged　upon　the　viaduct

at　Pont…Cysylltau；　he　snatched　a　few　day's　leisure　to　run　through

North　Wales；　of　which　he　afterwards　gave　a　glowing　account　to　his

correspondent。　　He　passed　by　Cader　Idris；　Snowdon；　and　Penmaen　Mawr。

〃Parts　of　the　country　we　passed　through；〃　he　says；　〃very　much

resemble　the　lofty　green　hills　and　woody　vales　of　Eskdale。　　In　other

parts　the　magnificent　boldness　of　the　mountains；　the　torrents；

lakes；　and　waterfalls；　give　a　special　character　to　the　scenery；

unlike　everything　of　the　kind　I　had　before　seen。　　The　vale　of

Llanrwst　is　peculiarly　beautiful　and　fertile。　　In　this　vale　is　the

celebrated　bridge　of　Inigo　Jones；　but　what　is　a　much　more

delightful　circumstance；　the　inhabitants　of　the　vale　are　the　most

beautiful　race　of　people　I　have　ever　beheld；　and　I　am　much

astonished　that　this　never　seems　to　have　struck　the　Welsh　tourists。

The　vale　of　Llangollen　is　very　fine；　and　not　the　least　interesting

object　in　it；　I　can　assure　you；　is　Davidson's　famous　aqueduct

＇Pont…Cysylltau＇；　which　is　already　reckoned　among　the　wonders　of

Wales。　　Your　old　acquaintance　thinks　nothing　of　having　three　or

four　carriages　at　his　door　at　a　time。〃*＇9＇　　It　seems　that；　besides

attending　to　the　construction　of　the　works；　Telford　had　to

organise　the　conduct　of　the　navigation　at　those　points　at　which　the

canal　was　open　for　traffic。　　By　the　middle　of　1797　he　states　that

twenty　miles　were　in　working　condition；　along　which　coal　and　lime

were　conveyed　in　considerable　quantifies；　to　the　profit　of　the

Company　and　the　benefit　of　the　public；　the　price　of　these　articles

having　already　in　some　places　been　reduced　twenty…five；　and　in

others　as　much　as　fifty；　per　cent。　　〃The　canal　affairs；〃