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instrument。 He doubtless felt within him the promptings of ambition；
such as every good workman feels； and at all events entertained the
desire of rising in his trade。 When his time was out； he accordingly
resolved to seek work in London； whither he made the journey on foot。
He soon found work at a cabinet…maker's； and remained with him for
some time； after which he set up business in a very small way on his
own account。 An accident which happened to him in the course of his
daily work； again proved his helper； by affording him a degree of
leisure which he at once proceeded to turn to some useful account。
Part of his business consisted in putting up water…closets； after a
method invented or improved by a Mr。 Allen； but the article was still
very imperfect； and Bramah had long resolved that if he could only
secure some leisure for the purpose； he would contrive something that
should supersede it altogether。 A severe fall which occurred to him
in the course of his business； and laid him up； though very much
against his will； now afforded him the leisure which he desired； and
he proceeded to make his proposed invention。 He took out a patent for
it in 1778； describing himself in the specification as 〃of Cross
Court； Carnaby Market ＇Golden Square＇； Middlesex； Cabinet Maker。〃 He
afterwards removed to a shop in Denmark Street； St。 Giles's； and
while there he made a further improvement in his invention by the
addition of a water cock； which he patented in 1783。 The merits of
the machine were generally recognised； and before long it came into
extensive use； continuing to be employed； with but few alterations；
until the present day。 His circumstances improving with the increased
use of his invention； Bramah proceeded to undertake the manufacture
of the pumps； pipes； &c。； required for its construction； and；
remembering his friend the Yorkshire blacksmith； who had made his
first tools for him out of the old files and razor…blades； he sent
for him to London to take charge of his blacksmith's department； in
which he proved a most useful assistant。 As usual； the patent was
attacked by pirates so soon as it became productive； and Bramah was
under the necessity； on more than one occasion； of defending his
property in the invention； in which he was completely successful。
We next find Bramah turning his attention to the invention of a lock
that should surpass all others then known。 The locks then in use were
of a very imperfect character； easily picked by dexterous thieves；
against whom they afforded little protection。 Yet locks are a very
ancient invention； though； as in many other cases； the art of making
them seems in a great measure to have become lost； and accordingly
had to be found out anew。 Thus the tumbler lockwhich consists in
the use of moveable impediments acted on by the proper key only； as
contradistinguished from the ordinary ward locks； where the
impediments are fixed appears to have been well known to the
ancient Egyptians； the representation of such a lock being found
sculptured among the bas…reliefs which decorate the great temple at
Karnak。 This kind of lock was revived； or at least greatly improved；
by a Mr。 Barron in 1774； and it was shortly after this time that
Bramah directed his attention to the subject。 After much study and
many experiments； he contrived a lock more simple； more serviceable；
as well as more secure； than Barron's； as is proved by the fact that
it has stood the test of nearly eighty years' experience；*
＇footnote。。。
The lock invented by Bramah was patented in 1784。 Mr。 Bramah himself
fully set forth the specific merits of the invention in his
Dissertation on the Construction of Locks。 In a second patent； taken
out by him in 1798； he amended his first with the object of
preventing the counterfeiting of keys； and suspending the office of
the lock until the key was again in the possession of the owner。 This
he effected by enabling the owner so to alter the sliders as to
render the lock inaccessible to such key if applied by any other
person but himself； or until the sliders had been rearranged so as to
admit of its proper action。 We may mention in passing that the
security of Bramah's locks depends on the doctrine of combinations；
or multiplication of numbers into each other； which is known to
increase in the most rapid proportion。 Thus； a lock of five slides
admits of 3；000 variations； while one of eight will have no less than
1；935；360 changes； in other words； that number of attempts at making
a key； or at picking it； may be made before it can be opened。
。。。＇
and still holds its ground。 For a long time； indeed； Bramah's lock
was regarded as absolutely inviolable； and it remained unpicked for
sixty…seven years until Hobbs the American mastered it in 1851。 A
notice had long been exhibited in Bramah's shop…window in Piccadilly；
offering 200L。 to any one who should succeed in picking the patent
lock。 Many tried； and all failed； until Hobbs succeeded； after
sixteen days' manipulation of it with various elaborate instruments。
But the difficulty with which the lock was picked showed that； for
all ordinary purposes； it might be pronounced impregnable。
The new locks were machines of the most delicate kind； the action of
which depended in a great measure upon the precision with which the
springs； sliders； levers； barrels； and other parts were finished。 The
merits of the invention being generally admitted； there was a
considerable demand for the locks； and the necessity thus arose for
inventing a series of original machine…tools to enable them to be
manufactured in sufficient quantities to meet the demand。 It is
probable； indeed； that； but for the contrivance of such tools； the
lock could never have come in to general use； as the skill of
hand…workmen； no matter how experienced； could not have been relied
upon for turning out the article with that degree of accuracy and
finish in all the parts which was indispensable for its proper
action。 In conducting the manufacture throughout； Bramah was greatly
assisted by Henry Maudslay； his foreman； to whom he was in no small
degree indebted for the contrivance of those tool…machines which
enabled him to carry on the business of lock…making with advantage
and profit。
Bramah's indefatigable spirit of invention was only stimulated to
fresh efforts by the success of his lock； and in the course of a few
years we find him entering upon a more important and original line of
action than he had yet ventured on。 His patent of 1785 shows the
direction of his studies。 Watt had invented his steam…engine； which
was coming into general use； and the creation of motive…power in
various other forms became a favourite subject of inquiry with
inventors。 Bramah's first invention with this object was his
Hydrostatic Machine； founded on the doctrine of the equilibrium of
pressure in fluids； as exhibited in the well known 'hydrostatic
paradox。' In his patent of 1785； in which he no longer describes
himself as Cabinet maker； but 'Engine maker' of Piccadilly； he
indicated many inventions； though none of them came into practical
use；such as a Hydrostatical Machine and Boiler； and the application
of the power produced by them to the drawing of carriages； and the
propelling of ships by a paddle…wheel fixed in the stern of the
vessel； of which drawings are annexed to the specification； but it
was not until 1795 that he patented his Hydrostatic or Hydraulic
Press。
Though the principle on which the Hydraulic Press is founded had long
been known； and formed the subject of much curious speculation； it
remained unproductive of results until a comparatively recent period；
when the idea occurred of applying it to mechanical purposes。 A
machine of the kind was indeed proposed by Pascal； the eminent
philosopher； in 1664； but more than a century elapsed before the
difficulties in the way of its construction were satisf