industrial biography-第58章

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usually　driven　by　a　water…wheel；　or　by　oxen　or　horses。　　The

tilt…hammer　was　another　form　in　which　it　was　used；　the　smaller　kinds

being　worked　by　the　foot。　　Among　Watt's　various　inventions；　was　a

tilt…hammer　of　considerable　power；　which　he　at　first　worked　by　means

of　a　water…wheel；　and　afterwards　by　a　steam　engine　regulated　by　a

fly…wheel。　　His　first　hammer　of　this　kind　was　120　lbs。　in　weight；　it

was　raised　eight　inches　before　making　each　blow。　　Watt　afterwards　made

a　tilt…hammer　for　Mr。　Wilkinson　of　Bradley　Forge；　of　7　1/2　cwt。；　and

it　made　300　blows　a　minute　。　　Other　improvements　were　made　in　the

hammer　from　time　to　time；　but　no　material　alteration　was　made　in　the

power　by　which　it　was　worked　until　Mr。　Nasmyth　took　it　in　hand；　and

applying　to　it　the　force　of　steam；　at　once　provided　the　worker　in

iron　with　the　most　formidable　of　machine…tools。　　This　important

invention　originated　as　follows：　　



In　the　early　part　of　1837；　the　directors　of　the　Great　Western

Steam…Ship　Company　sent　Mr。　Francis　Humphries；　their　engineer；　to

consult　Mr。　Nasmyth　as　to　some　engineering　tools　of　unusual　size　and

power；　which　were　required　for　the　construction　of　the　engines　of　the

〃Great　Britain〃　steamship。　　They　had　determined　to　construct　those

engines　on　the　vertical　trunk…engine　principle；　in　accordance　with

Mr。　Humphries'　designs；　and　very　complete　works　were　erected　by　them

at　their　Bristol　dockyard　for　the　execution　of　the　requisite

machinery；　the　most　important　of　the　tools　being　supplied　by　Nasmyth

and　Gaskell。　　The　engines　were　in　hand；　when　a　difficulty　arose　with

respect　to　the　enormous　paddle…shaft　of　the　vessel；　which　was　of　such

a　size　of　forging　as　had　never　before　been　executed。　　Mr。　Humphries

applied　to　the　largest　engineering　firms　throughout　the　country　for

tenders　of　the　price　at　which　they　would　execute　this　part　of　the

work；　but　to　his　surprise　and　dismay　he　found　that　not　one　of　the

firms　he　applied　to　would　undertake　so　large　a　forging。　　In　this

dilemma　he　wrote　to　Mr。　Nasmyth　on　the　24th　November；1838；　informing

him　of　this　unlooked…for　difficulty。　　〃I　find；〃　said　he；　〃there　is　not

a　forge…hammer　in　England　or　Scotland　powerful　enough　to　forge　the

paddle…shaft　of　the　engines　for　the　'Great　Britain！'　What　am　I　to　do？

Do　you　think　I　might　dare　to　use　cast…iron？〃



This　letter　immediately　set　Mr。　Nasmyth　a…thinking。　　How　was　it　that

existing　hammers　were　incapable　of　forging　a　wrought…iron　shaft　of

thirty　inches　diameter？　Simply　because　of　their　want　of　compass；　or

range　and　fall；　as　well　as　power　of　blow。　　A　few　moments'　rapid

thought　satisfied　him　that　it　was　by　rigidly　adhering　to　the　old

traditional　form　of　hand…hammerof　which　the　tilt；　though　driven

by　steam；　was　but　a　modificationthat　the　difficulty　had　arisen。

When　even　the　largest　hammer　was　tilted　up　to　its　full　height；　its

range　was　so　small；　that　when　a　piece　of　work　of　considerable　size

was　placed　on　the　anvil；　the　hammer　became　〃gagged；〃　and；　on　such　an

occasion；　where　the　forging　required　the　most　powerful　blow；　it

received　next　to　no　blow　at　all；the　clear　space　for　fall　being

almost　entirely　occupied　by　the　work　on　the　anvil。



The　obvious　remedy　was　to　invent　some　method；　by　which　a　block　of

iron　should　be　lifted　to　a　sufficient　height　above　the　object　on

which　it　was　desired　to　strike　a　blow；　and　let　the　block　fall　down

upon　the　work；guiding　it　in　its　descent　by　such　simple　means　as

should　give　the　required　precision　in　the　percussive　action　of　the

falling　mass。　　Following　out　this　idea；　Mr。　Nasmyth　at　once　sketched

on　paper　his　steam…hammer；　having　it　clearly　before　him　in　his　mind's

eye　a　few　minutes　after　receiving　Mr。　Humphries'　letter　narrating　his

unlooked…for　difficulty。　　The　hammer；　as　thus　sketched；　consisted　of；

first　an　anvil　on　which　to　rest　the　work；　second；　a　block　of　iron

constituting　the　hammer　or　blow…giving　part；　third；　an　inverted

steam…cylinder　to　whose　piston…rod　the　block　was　attached。　　All　that

was　then　required　to　produce　by　such　means　a　most　effective　hammer；

was　simply　to　admit　steam　in　the　cylinder　so　as　to　act　on　the　under

side　of　the　piston；　and　so　raise　the　block　attached　to　the

piston…rod；　and　by　a　simple　contrivance　to　let　the　steam　escape　and

so　permit　the　block　rapidly　to　descend　by　its　own　gravity　upon　the

work　then　on　the　anvil。　　Such；　in　a　few　words；　is　the　rationale　of　the

steam…hammer。



By　the　same　day's　post；　Mr。　Nasmyth　wrote　to　Mr。　Humphries；　inclosing

a　sketch　of　the　invention　by　which　he　proposed　to　forge　the　〃Great

Britain〃　paddle…shaft。　　Mr。　Humphries　showed　it　to　Mr。　Brunel；　the

engineer…inchief　of　the　company；　to　Mr。　Guppy；　the　managing　director；

and　to　others　interested　in　the　undertaking；　by　all　of　whom　it　was

heartily　approved。　　Mr。　Nasmyth　gave　permission　to　communicate　his

plans　to　such　forge　proprietors　as　might　feel　disposed　to　erect　such

a　hammer　to　execute　the　proposed　work；the　only　condition　which　he

made　being；　that　in　the　event　of　his　hammer　being　adopted；　he　was　to

be　allowed　to　supply　it　according　to　his　own　design。



The　paddle…shaft　of　the　〃Great　Britain〃　was；　however；　never　forged。

About　that　time；　the　substitution　of　the　Screw　for　the　Paddle…wheel

as　a　means　of　propulsion　of　steam…vessels　was　attracting　much

attention；　and　the　performances　of　the　〃Archimedes〃　were　so

successful　as　to　induce　Mr。　Brunel　to　recommend　his　Directors　to

adopt　the　new　power。　　They　yielded　to　his　entreaty。　　The　great　engines

which　Mr。　Humphries　had　designed　were　accordingly　set　aside；　and　he

was　required　to　produce　fresh　designs　of　engines　suited　for　screw

propulsion。　　The　result　was　fatal　to　Mr。　Humphries。　　The　labour；　the

anxiety；　and　perhaps　the　disappointment；　proved　too　much　for　him；　and

a　brain…fever　carried　him　off；　so　that　neither　his　great　paddle…shaft

nor　Mr。　Nasmyth's　steam…hammer　to　forge　it　was　any　longer　needed。



The　hammer　was　left　to　bide　its　time。　　No　forge…master　would　take　it

up。　　The　inventor　wrote　to　all　the　great　firms；　urging　its　superiority

to　every　other　tool　for　working　malleable　iron　into　all　kinds　of

forge　work。　　Thus　he　wrote　and　sent　illustrative　sketches　of　his

hammer　to　Accramans　and　Morgan　of　Bristol；　to　the　late　Benjamin　Hick

and　Rushton　and　Eckersley　of　Bolton；　to　Howard　and　Ravenhill　of

Rotherhithe；　and　other　firms；　but　unhappily　bad　times　for　the　iron

trade　had　set　in；　and　although　all　to　whom　he　communicated　his　design

were　much　struck　with　its　simplicity　and　obvious　advantages；　the

answer　usually　given　was〃We　have　not　orders　enough　to　keep　in

work　the　forge…hammers　we　already　have；　and　we　do　not　desire　at

present　to　add　any　new　ones；　however　improved。〃　　At　that　time　no

patent　had　been　taken　out　for　the　invention。　　Mr。　Nasmyth　had　not　yet

saved　money　enough　to　enable　him　to　do　so　on　his　own　account；　and　his

partner　declined　to　spend　money　upon　a　tool　that　no　engineer　would

give　the　firm　an　order　for。　　No　secret　was　made　of　the　invention；　and；

excepting　to　its　owner；　it　did　not　seem　to　be　worth　one　farthing。



Such　was　the　unpromising　state　of　affairs；　when　M。　Schneider；　of　the

Creusot　Iron　Works　in　France；　called　at　the　Patricroft　works　together

with　his　practical　mechanic　M。　Bourdon；　for　the　purpose　of　ordering

some　tools　of　the　firm。　　Mr。　Nasmyth　was　absent　on　a　journey　at　the

time；　but　his　partner；　Mr。　Gaskell；　as　an　act　of　courtesy　to　the

strangers；　took　the　opportunity　of　showing　them　all　that　was　new　and

interesting　in　regard　to　mechanism　about　the　works。　　And　among　other

things；　Mr。　Gaskell　brought　out　his　partner's　sketch　or　〃Scheme

book；〃　which　lay　in　a　drawer　in　the　office；　and　showed　them　the

design　of　the　Steam　Hammer；　which　no　English　firm　would　adopt。　　They

were　much　struck　with　its　simplicity　and　practical　utility；　and　M。

Bourdon　took　careful　note　of　its　arrangements。　　Mr。　Nasmyth　on　his

return　was　informed　of　the　visit　of　MM。　Schneider　and　Bourdon；　but

the　circumstance　of　their　having　inspected　the　design　of　his

steam…hammer　seems　to　have　been　regarded　by　his　partner　as　too

trivial　a　matter　to　be　repeated　to　him；　and　he　knew　nothing　of　the

circumstance　until　his　visit　to　France　in　April；　1840。　　When　passing

through　the　works　at　Creusot　with　M。　Bourdon；　Mr。　Nasmyth　saw　a　crank

shaft　of　unusual　size；　not　only　forged　in　the　piece；　but　punched。　　He

immediately　asked；　〃How　did　you　forge　that　shaft？〃　　M。　Bourdon's

answer　was；　〃Why；　with　your　hammer；　to　be　sure！〃　　Great　indeed　was

Nasmyth's　surprise；　for　he　had　never　yet　seen　the　hammer；　except　in

his　own　drawing！　　A　little　explanation　soon　cleared　all　up。　　M。　Bourdon

said　he　had　been　so　much　struck　with　the　ingenuity　and　simplicity　of

the　arrangement；　that　he　had　no　sooner　returned　than　he　set　to　work；

and　had　a　hammer　made　in　general　accordance　with　the　design　Mr。

Gaskell　had　shown　him；　and　that　its　performances　had　answered　his

every　expectation。　　He　then　took　Mr。　Nasmyth　to　see　the　steam…hammer；

and　great　was　his　delight　at　seeing　the　child　of　his　brain　in　full

and　active　work。　　It　was　not；　according　to　Mr。　Nasmyth's　ideas；　quite

perfect；　and　he　readily　suggested　several　improvements；　conformable

with　the　original　design；　which　M。　Bourdon　forthwith　adopted。



On　reaching　England；　Mr。　Nasmyth　at　once　wrote　to　his　partner　telling

him　what　he　had　seen；　and　urging　that　the　taking　out　of　a　patent　for

the　protection　of　the　invention　ought　no　longer　to　be　deferred。　　But

trade　was　still　very　much　depressed；　and　as　the　Patricroft　firm

needed　all　their　capital　to　carry　on　their　business；　Mr。　Gaskell

objected　to　lock　any　of　it　up　in　engineering　novelties。　　Seeing

himself　on　the　brink　of　losing　his　property　in　the　invention；　Mr。

Nasmyth　applied　to　his　brother…in…law；　William　Bennett；　Esq。；　who

advanced　him　the　requisite　money　for　the　purposeabout　280L。；

and　the　patent　was　secured　in　June　1840。　　The　first　hammer；　of　30

cwt。；　was　made　for　the　Patricroft　works；　with　the　consent　of　the

partners；　and　in　the　course　of　a　few　weeks　it　was　in　full　work。　　The

precision　and　beauty　of　its　actionthe　perfect　ease　with　which　it

was　managed；　and　the　untiring　force　of　its　percussive　blowswere

the　admiration　of　all　who　saw　it；　and　from　that　moment　the

steam…hammer　became　a　recognised　power　in　modern　mechanics。　　The

variety　or　gradation　of　its　blows　was　such；　that　it　was　found

practicable　to　manipulate　a　hammer　of　ten　tons　as　easily　as　if　it　had

only　been　of　ten　ounces　weight。　　It　was　under　such　complete　control

that　while　descending　with　its　greatest　momentum；　it　could　be

arrested　at　any　point　with　even　greater　ease　than　any　instrument　used

by　hand。　　While　capable　of　forging　an　Armstrong　hundred…pounder；　or

the　sheet…anchor　for　a　ship　of　the　line；　it　could　hammer　a　nail；　or

crack　a　nut　without　bruising　the　kernel。　　When　it　came　into　general

use；　the　facilities　which　it　afforded　for　executing　all　kinds　of

forging　had　the　effect　of　greatly　increasing　the　quantity　of　work