industrial biography- 第48部分

　＇footnote。。。

Machines　approuvees　par　l'　Academie；　1733。

　。。。＇

who　showed　how　a　lathe　could　turn　all　sorts　of　irregular　figures　by

means　of　tracers；　and　of　Grand　Jean；　Morin；*

　＇footnote。。。

L'Art　de　Tourner　en　perfection；　49。

　。。。＇

　Plumier；　Bergeron；　and　many　other　writers。



The　work　of　Plumier　is　especially　elaborate；　entering　into　the

construction　of　the　lathe　in　its　various　parts；　the　making　of　the

tools　and　cutters；　and　the　different　motions　to　be　given　to　the

machine　by　means　of　wheels；　eccentrics；　and　other　expedients；　amongst

which　may　be　mentioned　one　very　much　resembling　the　slide　rest　and

planing…machine　combined。*

　＇footnote。。。

It　consisted　of　two　parallel　bars　of　wood　or　iron　connected　together

at　both　extremities　by　bolts　or　keys　of　sufficient　width　to　admit　of

the　article　required　to　be　planed。　　A　moveable　frame　was　placed

between　the　two　bars；　motion　being　given　to　it　by　a　long　cylindrical

thread　acting　on　any　tool　put　into　the　sliding　frame；　and；

consequently；　causing　the　screw；　by　means　of　a　handle　at　each　end　of

it；　to　push　or　draw　the　point　or　cutting…edge　of　the　tool　either

way。Mr。　George　Rennie's　Preface　to　Buchanan's　Practical　Essays　on

Mill　Work；　3rd　Ed。　xli。

　。。。＇

　From　this　work　it　appears　that　turning　had　long　been　a　favourite

pursuit　in　France　with　amateurs　of　all　ranks；　who　spared　no　expense

in　the　contrivance　and　perfection　of　elaborate　machinery　for　the

production　of　complex　figures。*

　＇footnote。。。

Turning　was　a　favourite　amusement　amongst　the　French　nobles　of　last

century；　many　of　whom　acquired　great　dexterity　in　the　art；　which　they

turned　to　account　when　compelled　to　emigrate　at　the　Revolution。　　Louis

XVI。　himself　was　a　very　good　locksmith；　and　could　have　earned　a　fair

living　at　the　trade。　　Our　own　George　III。　was　a　good　turner；　and　was

learned　in　wheels　and　treadles；　chucks　and　chisels。　　Henry　Mayhew

says；　on　the　authority　of　an　old　working　turner；　that；　with　average

industry；　the　King　might　have　made　from　40s。　to　50s。　a…week　as　a　hard

wood　and　ivory　turner。　　Lord　John　Hay；　though　one…armed；　was　an　adept

at　the　latter；　and　Lord　Gray　was　another　capital　turner。　　Indeed　the

late　Mr。　Holtzapffel's　elaborately　illustrated　treatise　was　written

quite　as　much　for　amateurs　as　for　working　mechanics。　　Among　other

noble　handicraftsmen　we　may　mention　the　late　Lord　Douglas；　who

cultivated　bookbinding。　　Lord　Traquair's　fancy　was　cutlery；　and　one

could　not　come　to　him　in　a　more　welcome　fashion　than　with　a　pair　of

old　razors　to　set　up。

　。。。＇

There　was　at　that　time　a　great　passion　for　automata　in　France；　which

gave　rise　to　many　highly　ingenious　devices；　such　as　Camus's　miniature

carriage　（made　for　Louis　XIV。　when　a　child）；　Degennes'　mechanical

peacock；　Vancanson's　duck；　and　Maillardet's　conjuror。　　It　had　the

effect　of　introducing　among　the　higher　order　of　artists　habits　of

nice　and　accurate　workmanship　in　executing　delicate　pieces　of

machinery；　and　the　same　combination　of　mechanical　powers　which　made

the　steel　spider　crawl；　the　duck　quack；　or　waved　the　tiny　rod　of　the

magician；　contributed　in　future　years　to　purposes　of　higher

import；the　wheels　and　pinions；　which　in　these　automata　almost

eluded　the　human　senses　by　their　minuteness；　reappearing　in　modern

times　in　the　stupendous　mechanism　of　our　self…acting　lathes；

spinning…mules；　and　steam…engines。



〃In　our　own　country；〃　says　Professor　Willis；　〃the　literature　of　this

subject　is　so　defective　that　it　is　very　difficult　to　discover　what

progress　we　were　making　during　the　seventeenth　and　eighteenth

centuries。〃*

　＇footnote。。。

Professor　WILLIS；　Lectures　on　the　Results　of　the　Great　Exhibition　of

1851；　lst　series；　p。　306。

　。。。＇

We　believe　the　fact　to　be；　that　the　progress　made　in　England　down　to

the　end　of　last　century　had　been　very　small　indeed；　and　that　the

lathe　had　experienced　little　or　no　improvement　until　Maudslay　took　it

in　hand。　　Nothing　seems　to　have　been　known　of　the　slide　rest　until　he

re…invented　it　and　applied　it　to　the　production　of　machinery　of　a　far

more　elaborate　character　than　had　ever　before　been　contemplated　as

possible。　　Professor　Willis　says　that　Bramah's；　in　other　words

Maudslay's；　slide　rest　of　1794　is　so　different　from　that　described　in

the　French　'Encyclopedie　in　1772；　that　the　two　could　not　have　had　a

common　origin。　　We　are　therefore　led　to　the　conclusion　that　Maudslay's

invention　was　entirely　independent　of　all　that　had　gone　before；　and

that　he　contrived　it　for　the　special　purpose　of　overcoming　the

difficulties　which　he　himself　experienced　in　turning　out　duplicate

parts　in　large　numbers。　　At　all　events；　he　was　so　early　and　zealous　a

promoter　of　its　use；　that　we　think　he　may；　in　the　eyes　of　all

practical　mechanics；　stand　as　the　parent　of　its　introduction　to　the

workshops　of　England。



It　is　unquestionable　that　at　the　time　when　Maudslay　began　the

improvement　of　machine…tools；　the　methods　of　working　in　wood　and

metals　were　exceedingly　imperfect。　　Mr。　William　Fairbairn　has　stated

that　when　he　first　became　acquainted　with　mechanical　engineering；

about　sixty　years　ago；　there　were　no　self…acting　tools；　everything

was　executed　by　hand。　　There　were　neither　planing；　slotting；　nor

shaping　machines；　and　the　whole　stock　of　an　engineering　or　machine

establishment　might　be　summed　up　in　a　few　ill…constructed　lathes；　and

a　few　drills　and　boring　machines　of　rude　construction。*

　＇footnote。。。

Address　delivered　before　the　British　Association　at　Manchester　in

1861；　and　Useful　Information　for　Engineers；　1st　series；　p。　22。

　。。。＇

Our　mechanics　were　equally　backward　in　contrivances　for　working　in

wood。　　Thus；　when　Sir　Samuel　Bentham　made　a　tour　through　the

manufacturing　districts　of　England　in　1791；　he　was　surprised　to　find

how　little　had　been　done　to　substitute　the　invariable　accuracy　of

machinery　for　the　uncertain　dexterity　of　the　human　hand。　　Steam…power

was　as　yet　only　employed　in　driving　spinning…machines；　rolling

metals；　pumping　water；　and　such　like　purposes。　　In　the　working　of　wood

no　machinery　had　been　introduced　beyond　the　common　turning…lathe　and

some　saws；　and　a　few　boring　tools　used　in　making　blocks　for　the　navy。

Even　saws　worked　by　inanimate　force　for　slitting　timber；　though　in

extensive　use　in　foreign　countries；　were　nowhere　to　be　found　in　Great

Britain。*

　＇footnote。。。

Life　of　Sir　Samuel　Bentham；　97…8。

　。。。＇

As　everything　depended　on　the　dexterity　of　hand　and　correctness　of

eye　of　the　workmen；　the　work　turned　out　was　of　very　unequal　merit；

besides　being　exceedingly　costly。　　Even　in　the　construction　of

comparatively　simple　machines；　the　expense　was　so　great　as　to　present

a　formidable　obstacle　to　their　introduction　and　extensive　use；　and

but　for　the　invention　of　　machine…making　tools；　the　use　of　the

steam…engine　in　the　various　forms　in　which　it　is　now　applied　for　the

production　of　power　could　never　have　become　general。



In　turning　a　piece　of　work　on　the　old…fashioned　lathe；　the　workman

applied　and　guided　his　tool　by　means　of　muscular　strength。　　The　work

was　made　to　revolve；　and　the　turner；　holding　the　cutting　tool　firmly

upon　the　long；　straight；　guiding　edge　of　the　rest；　along　which　he

carried　it；　and　pressing　its　point　firmly　against　the　article　to　be

turned；　was　thus　enabled　to　reduce　its　surface　to　the　required　size

and　shape。　　Some　dexterous　turners　were　able；　with　practice　and

carefulness；　to　execute　very　clever　pieces　of　work　by　this　simple

means。　　But　when　the　article　to　be　turned　was　of　considerable　size；

and　especially　when　it　was　of　metal；　the　expenditure　of　muscular

strength　was　so　great　that　the　workman　soon　became　exhausted。　　The

slightest　variation　in　the　pressure　of　the　tool　led　to　an

irregularity　of　surface；　and　with　the　utmost　care　on　the　workman's

part；　he　could　not　avoid　occasionally　cutting　a　little　too　deep；　in

consequence　of　which　he　must　necessarily　go　over　the　surface　again；

to　reduce　the　whole　to　the　level　of　that　accidentally　cut　too　deep；

and　thus　possibly　the　job　would　be　altogether　spoiled　by　the　diameter

of　the　article　under　operation　being　made　too　small　for　its　intended

purpose。



The　introduction　of　the　slide　rest　furnished　a　complete　remedy　for

this　source　of　imperfection。　　The　principle　of　the　invention　consists

in　constructing　and　fitting　the　rest　so　that；　instead　of　being

screwed　down　to　one　place；　and　the　tool　in　the　hands　of　the　workman

travelling　over　it；　the　rest　shall　itself　hold　the　cutting　tool

firmly　fixed　in　it；　and　slide　along　the　surface　of　the　bench　in　a

direction　exactly　parallel　with　the　axis　of　the　work。　　Before　its

invention　various　methods　had　been　tried　with　the　object　of　enabling

the　work　to　be　turned　true　independent　of　the　dexterity　of　the

workman。　　Thus；　a　square　steel　cutter　used　to　be　firmly　fixed　in　a

bed；　along　which　it　was　wedged　from　point　to　point　of　the　work；　and

tolerable　accuracy　was　in　this　way　secured。　　But　the　slide　rest　was

much　more　easily　managed；　and　the　result　was　much　more　satisfactory。

All　that　the　workman　had　to　do；　after　the　tool　was　firmly　fitted　into

the　rest；　was　merely　to　turn　a　screw…handle；　and　thus　advance　the

cutter　along　the　face　of　the　work　as　required；　with　an　expenditure　of

strength　so　slight　as　scarcely　to　be　appreciable。　　And　even　this

labour　has　now　been　got　rid　of；　for；　by　an　arrangement　of　the

gearing；　the　slide　itself　has　been　made　self…acting；　and　advances

with　the　revolution　of　the　work　in　the　lathe；　which　thus　supplies　the

place　of　the　workman's　hand。　　The　accuracy　of　the　turning　done　by　this

beautiful　yet　simple　arrangement　is　as　mechanically　perfect　as　work

can　be。　　The　pair　of　steel　fingers　which　hold　the　cutting　tool　firmly

in　their　grasp　never　tire；　and　it　moves　along　the　metal　to　be　cut

with　an　accuracy　and　precision　which　the　human　hand；　however　skilled；

could　never　equal。



The　effects　of　the　introduction　of　the　slide　rest　were　very　shortly

felt　in　all