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第55章

industrial biography-第55章

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secured this invention in 1801; he also proposed sundry improvements

in the boilers; as well as modifications in various parts of the

engine; with the object of effecting greater simplicity and

directness of action。



In his patent of 1802; we find Bramah making another great stride in

mechanical invention; in his tools 〃for producing straight; smooth;

and parallel surfaces on wood and other materials requiring truth; in

a manner much more expeditious and perfect than can be performed by

the use of axes; saws; planes; and other cutting instruments used by

hand in the ordinary way。〃  The specification describes the object of

the invention to be the saving of manual labour; the reduction in the

cost of production; and the superior character of the work executed。

The tools were fixed on frames driven by machinery; some moving in a

rotary direction round an upright shaft; some with the shaft

horizontal like an ordinary wood…turning lathe; while in others the

tools were fixed on frames sliding in stationary grooves。  A

wood…planing machine*

 'footnote。。。

Sir Samuel Bentham and Marc Isambard Brunel subsequently

distinguished themselves by the invention of wood…working machinery;

full accounts of which will be found in the Memoirs of the former by

Lady Bentham; and in the Life of the latter by Mr。 Beamish。

 。。。'

was constructed on the principle of this invention at Woolwich

Arsenal; where it still continues in efficient use。  The axis of the

principal shaft was supported on a piston in a vessel of oil; which

considerably diminished the friction; and it was so contrived as to

be accurately regulated by means of a small forcing…pump。  Although

the machinery described in the patent was first applied to working on

wood; it was equally applicable to working on metals; and in his own

shops at Pimlico Bramah employed a machine with revolving cutters to

plane metallic surfaces for his patent locks and other articles。  He

also introduced a method of turning spherical surfaces; either convex

or concave; by a tool moveable on an axis perpendicular to that of

the lathe; and of cutting out concentric shells by fixing in a

similar manner a curved tool of nearly the same form as that employed

by common turners for making bowls。  〃In fact;〃 says Mr。 Mallet;

〃Bramah not only anticipated; but carried out upon a tolerably large

scale in his own worksfor the construction of the patent hydraulic

press; the water…closet; and his locksa surprisingly large

proportion of our modern tools。〃*

 'footnote。。。

〃Record of the International Exhibition; 1862。〃  Practical Mechanic's

Journal; 293。

 。。。'

His remarkable predilection in favour of the use of hydraulic

arrangements is displayed in his specification of the surface…planing

machinery; which includes a method of running pivots entirely on a

fluid; and raising and depressing them at pleasure by means of a

small forcing…pump and stop…cock;though we are not aware that any

practical use has ever been made of this part of the invention。



Bramah's inventive genius displayed itself alike in small things as

in greatin a tap wherewith to draw a glass of beer; and in a

hydraulic machine capable of tearing up a tree by the roots。  His

powers of contrivance seemed inexhaustible; and were exercised on the

most various subjects。  When any difficulty occurred which mechanical

ingenuity was calculated to remove; recourse was usually had to

Bramah; and he was rarely found at a loss for a contrivance to

overcome it。  Thus; when applied to by the Bank of England in 1806; to

construct a machine for more accurately and expeditiously printing

the numbers and date lines on Bank notes; he at once proceeded to

invent the requisite model; which he completed in the course of a

month。  He subsequently brought it to great perfection the figures in

numerical succession being changed by the action of the machine

itself;and it still continues in regular use。  Its employment in the

Bank of England alone saved the labour of a hundred clerks; but its

chief value consisted in its greater accuracy; the perfect legibility

of the figures printed by it; and the greatly improved check which it

afforded。



We next find him occupying himself with inventions connected with the

manufacture of pens and paper。  His little pen…making machine for

readily making quill pens long continued in use; until driven out by

the invention of the steel pen; but his patent for making paper by

machinery; though ingenious; like everything he did; does not seem to

have been adopted; the inventions of Fourdrinier and Donkin in this

direction having shortly superseded all others。  Among his other minor

inventions may be mentioned his improved method of constructing and

sledging carriage…wheels; and his improved method of laying

water…pipes。  In his specification of the last…mentioned invention; he

included the application of water…power to the driving of machinery

of every description; and for hoisting and lowering goods in docks

and warehouses;since carried out in practice; though in a different

manner; by Sir William Armstrong。*

 'footnote。。。

In this; as in other methods of employing power; the moderns had been

anticipated by the ancients; and though hydraulic machinery is a

comparatively recent invention in England; it had long been in use

abroad。  Thus we find in Dr。 Bright's Travels in Lower Hungary a full

description of the powerful hydraulic machinery invented by M。 Holl;

Chief Engineer of the Imperial Mines; which had been in use since the

year 1749; in pumping water from a depth of 1800 feet; from the

silver and gold mines of Schemnitz and Kremnitz。  A head of water was

collected by forming a reservoir along the mountain side; from which

it was conducted through water…tight cast…iron pipes erected

perpendicularly in the mine…shaft。  About forty…five fathoms down; the

water descending through the pipe was forced by the weight of the

column above it into the bottom of a perpendicular cylinder; in which

it raised a water…tight piston。  When forced up to a given point a

self…acting stop…cock shut off the pressure of the descending column;

while a self…acting valve enabled the water contained in the cylinder

to be discharged; on which the piston again descended; and the

process was repeated like the successive strokes of a steam…engine。

Pump…rods were attached to this hydraulic apparatus; which were

carried to the bottom of the shaft; and each worked a pump at

different levels; raising the water stage by stage to the level of

the main adit。  The pumps of these three several stages each raised

1790 cubic feet of water from a depth of 600 feet in the hour。  The

regular working of the machinery was aided by the employment of a

balance…beam connected by a chain with the head of the large piston

and pump…rods; and the whole of these powerful machines by means of

three of which as much as 789;840 gallons of water were pumped out of

the mines every 24 hours  were set in operation and regulated

merely by the turning of a stopcock。  It will be observed that the

arrangement thus briefly described was equally applicable to the

working of machinery of all kinds; cranes; &c。; as well as pumps; and

it will be noted that; notwithstanding the ingenuity of Bramah;

Armstrong; and other eminent English mechanics; the Austrian engineer

Holl was thus decidedly beforehand with them in the practical

application of the principles of hydrostatics。

 。。。'

In this; as in many other matters; Bramah shot ahead of the

mechanical necessities of his time; and hence many of his patents (of

which he held at one time more than twenty) proved altogether

profitless。  His last patent; taken out in 1814; was for the

application of Roman cement to timber for the purpose of preventing

dry rot。



Besides his various mechanical pursuits; Bramah also followed to a

certain extent the profession of a civil engineer; though his more

urgent 

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