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this arrangement was； that； even supposing the packing could be made
sufficiently tight to resist the passage of the water urged by the
tremendous pressure from beneath； such was the grip which the
compressed material took of the ram of the press； that it could not
be got to return down after the water pressure had been removed。
In this dilemma； Bramah's ever…ready workman； Henry Maudslay； came to
his rescue。 The happy idea occurred to him of employing the pressure
of the water itself to give the requisite water…tightness to the
collar。 It was a flash of common…sense genius beautiful through its
very simplicity。 The result was Maudslay's self…tightening collar；
the action of which a few words of description will render easily
intelligible。 A collar of sound leather； the convex side upwards and
the concave downwards； was fitted into the recess turned out in the
neck of the press…cylinder； at the place formerly used as a
stuffing…box 。 Immediately on the high pressure water being turned
on； it forced its way into the leathern concavity and 'flapped out'
the bent edges of the collar； and； in so doing； caused the leather to
apply itself to the surface of the rising ram with a degree of
closeness and tightness so as to seal up the joint the closer exactly
in proportion to the pressure of the water in its tendency to escape。
On the other hand； the moment the pressure was let off and the ram
desired to return； the collar collapsed and the ram slid gently down；
perfectly free and yet perfectly water…tight。 Thus； the former
tendency of the water to escape by the side of the piston was by this
most simple and elegant self…adjusting contrivance made instrumental
to the perfectly efficient action of the machine； and from the moment
of its invention the hydraulic press took its place as one of the
grandest agents for exercising power in a concentrated and tranquil
form。
Bramah continued his useful labours as an inventor for many years。
His study of the principles of hydraulics； in the course of his
invention of the press； enabled him to introduce many valuable
improvements in pumping…machinery。 By varying the form of the piston
and cylinder he was enabled to obtain a rotary motion；*
＇footnote。。。
Dr。 Thomas Young； in his article on Bramah in the Encyclopaedia
Britannica； describes the 〃rotative principle〃 as consisting in
making the part which acts immediately on the water in the form of a
slider； 〃sweeping round a cylindrical cavity； and kept in its place
by means of an eccentric groove； a contrivance which was probably
Bramah's own invention； but which had been before described； in a
form nearly similar； by Ramelli； Canalleri； Amontons； Prince Rupert；
and Dr。 Hooke。
。。。＇
which he advantageously applied to many purposes。 Thus he adopted it
in the well known fire…engine； the use of which has almost become
universal。 Another popular machine of his is the beer…pump； patented
in 1797； by which the publican is enabled to raise from the casks in
the cellar beneath； the various liquors sold by him over the counter。
He also took out several patents for the improvement of the
steam…engine； in which； however； Watt left little room for other
inventors； and hence Bramah seems to have entertained a grudge
against Watt； which broke out fiercely in the evidence given by him
in the case of Boulton and Watt versus Hornblower and Maberly； tried
in December 1796。 On that occasion his temper seems to have got the
better of his judgment； and he was cut short by the judge in the
attempt which he then made to submit the contents of the pamphlet
subsequently published by him in the form of a letter to the judge
before whom the case was tried。*
＇footnote。。。
A Letter to the Right Hon。 Sir James Eyre； Lord Chief Justice
of the Common Pleas； on the subject of the cause Boulton and
Watt v。 Hornblower and Maberly； for Infringement on Mr。 Watt's Patent
for an Improvement of the Steam Engine。 By Joseph Bramah； Engineer。
London； 1797。
。。。＇
In that pamphlet he argued that Watt's specification had no definite
meaning； that it was inconsistent and absurd； and could not possibly
be understood； that the proposal to work steam…engines on the
principle of condensation was entirely fallacious； that Watt's method
of packing the piston was 〃monstrous stupidity；〃 that the engines of
Newcomen （since entirely superseded） were infinitely superior； in all
respects； to those of Watt； conclusions which； we need scarcely
say； have been refuted by the experience of nearly a century。
On the expiry of Boulton and Watt's patent； Bramah introduced several
valuable improvements in the details of the condensing engine； which
had by that time become an established power；the most important of
which was his 〃four…way cock；〃 which he so arranged as to revolve
continuously instead of alternately； thus insuring greater precision
with considerably less wear of parts。 In the same patent by which he
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