A NEW AND PECULIAR ART OR METHOD OF CONSTRUCTING STEAM ENGINES, PUMPS, AND OTHER HYDRAULIC MACHINES
Year: 1798

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
DICKSON, late of Dockhead, in the County of Surry, but now of Narrow
Wall, in the Parish of Lambeth, in the said County, Engineer, send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent under the Great Seal of Great Britain, bearing date the
Fourteenth day of July, in the thirty-eighth year of His reign, give and grant
unto me, the said John Dickson, His special licence, full power, sole privilege
and authority, that I, the said John Dickson, during the term of years therein
expressed, should and lawfully might make, use, exercise, and vend, within
England, Wales, and the Town of Berwick-upon-Tweed, my Invention of "A
NEW AND PECULIAR ART OR METHOD OF CONSTRUCTING STEAM ENGINES, PUMPS, AND
OTHER HYDRAULIC MACHINES;" in which said Letters Patent there is contained
a proviso obliging me, the said John Dickson, by an instrument in writing
under my hand and seal, to particularly describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, and
cause the same to be inrolled in His Majesty's High Court of Chancery
within one calendar month next and immediately after the date of the said
Letters Patent, as in and by the said Letters Patent, reference being thereunto
had, may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Dickson, do hereby declare that the nature of my said Invention of a
new and particular Art or Method of Improving and Constructing Steam
Engines, Pumps, and other Hydraulic Machines, and the manner in which the
same is to be performed, is particularly described and ascertained in the manner
following, that is to say :-

page_text: First, there are two vessels in the form of cylinders fitted into each other,
so as to have a space between them for a third vessel or cylinder to move in
without touching the sides of either of them; this space between the sides of
the two vessels to be filled with quicksilver or other metallic bodies in a fluid
state.
Secondly, the middle or moving cylinder is to be close at top, and made as
thin and light as possible, so as to be strong enough to resist the pressure of
the air or steam which is to act upon it, and is to be moved up and down
instead of a peston, as in other engines, and must be at least three feet longer
than the intended stroke of the engine, because it has to pass over the inside
cylinder, which stands at least thirty-one inches higher than the surface of the
quicksilver in the outside cylinder
Thirdly, the outside cylinder must be so much longer than the length of the
stroke of the engine or motion of the middle cylinder, so that the mouth
of the middle cylinder may be immersed a proper depth in the quicksilver
which stands in the space between. the inside and outside cylinders, so as to
counterbalance or resist the steam which acts in the inside of it, and to prevent
the steam making. its escape past the sides of the vessel.
Fourthly, there must be a cup or receiver on the top of the outside, cylinder
sufficiently large to receive a quantity of. quicksilver, which is protruded by the
immersing of the middle cylinder. therein, which displaces as much of the
quicksilver as the bulk of the metal in that part of the cylinder so immersed..
Fifthly, the moving, cylinder to be connected to the beam by rods, chains, or
otherwise, or to any other apparatus that may be used instead of a beam for
the purpose of doing the-work-the engine is intended to perform.
Sixthly, there are two pipes, or communications made. in proportion to the
sizes of the engines, which are fixed in the inside of the inside cylinder; the,
one of these pipes is to admit steam, the other to be used as an eduction pipe..
At the top of these pipes, the ends of which are fixed to a flaunch which
covers, the top of the inside cylinder, are two valves one for admitting steam
into the moving cylinder, the other to be used as an exhausting, valve, or,
snifting clack, which suffers..the steam to pass from the moving, cylinder. into
the eduction pipe when it is wanted to be condensed. At the bottom of each
of these pipes is a stuffing box,, that the rods which open and shut the valves
work through; these boxes being packed with hemp or any other elastic
substance, on purpose to keep the spaces round the rods steam and air tight.
Seventhly; there is a jet of cold water introduced at the time when the
steam is wanted to be..condensed in the same manner as in other engines,
up through the eduction pipe, which is placed in the inside of the cylinder

page_text: Eighthly, this water, which is thrown in to condense the steam, along with
the air that is contained therein, is protruded by a quantity of steam that is.
suffered to pass through the snifting clack for that
purpose.
Ninthly, in cases where engines are to be applied to make a rotative
motion, I introduce a fly wheel to act on a different principle to that of the
common ones; that is to say, there is a case of wood, iron, or any other
substance, made strong enough to resist the pressure of the atmosphere that is
to act upon it, there being a vacuum in the internal part of it... This case is
made large enough to contain a wheel of whatever size may be wanted to
work therein. Opposite the center of this case is a stuffing box on each side,
that suffers the shaft or axle of the wheel to turn freely therein. These boxes
are to be packed with hemp, or any other elastic substance, on purpose to keep
it air-tight. I likewise connect a small air pump, to connect with. any part of
the inside of this vessel or case; on purpose to exhaust the air that is contained
in it at the time the engine begins to work. This small pump is connected.
with the engines themselves, or otherwise, which, being worked, keeps a
vacuum in the vessel during the working of the engine. This being done, the
fly wheel meets with no resistance from the external air, which in common
cases very much impedes the motion.
In witness whereof, I, the said John Dickson, have hereunto set my hand
and seal, this Ninth day of August, in the year of our Lord One thousand
seven hundred and ninety-eight.
THE EXPLANATION TO THE PLAN HEREUNTO ANNEXED.
Ź
A, A, the outside cylinder. B, B, the inside cylinder. D, D, the space
between the outside and inside cylinder, which is to be filled with quick-
silver. C, C, the middle or moving cylinder, which moves in the space
between the outside and inside cylinder amongst the quicksilver, and acts
instead of a piston. P, P, the cup or receiver upon the top of the outside
cylinder, which receives the quicksilver from the space between the outside
and inside cylinder when protruded by the immersion of the middle or moving
cylinder therein. F, the piston rod which connects the moving cylinder to the
beam. E, E, the steam pipe for conducting the steam from the boiler into the
moving cylinder. .I, the steam valve, which suffers the steam to pass when
wanted to be introduced into the moving cylinder. G, G, the eduction pipe.
S, the exhausting valve or snifting clack. L, L, the two rods that open the
exhausting and steam valves. X, X, the two stuffing boxes upon the steam
and eduction pipes. N, the cock that induces the jet of water up through
the eduction pipe at the time the steam is wanted to be condensed.

page_text: Figure Second: L, M, R, S, représents a case of iron made hollow, and
large enough to admit a wheel of any size intended to turn therein, to answer
the purpose of a fly wheel. G, G, the shaft of the fly wheel. W, W, the
wheel placed in the inside of a case. P, P, two brass bearings which the
gudgeons of the wheel turn upon. C, C, two stuffing boxes; one on each side
of the case being packed with hemp round the gudgeon of the fly wheel on
purpose to keep it air-tight. A, B, a small air pump which exhausts the air
that is in the case while the wheel is moving.