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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