IMPROVEMENTS IN MACHINERY FOR PROPELLING
Year: 1854

page_text: LETTERS PATENT to Thomas Scott, of Brighton, in the County of
Sussex, Gentleman, for the Invention of "IMPROVEMENTS IN MACHINERY
FOR PROPELLING."
Sealed the 22nd September 1854, and dated the 3rd April 1854.
PROVISIONAL SPECIFICATION left by the said Thomas Scott at the
Office of the Commissioners of Patents, with his Petition, on the 3rd
April 1854.
I, THOMAS SCOTT, do hereby declare the nature of the said Invention for
"IMPROVEMENTS IN MACHINERY FOR PROPELLING " to be as follows:-
I employ a steam cylinder and a piston, which is connected with another
piston fitted to and working in another cylinder of larger diameter, one side
of which latter piston is exposed to the atmosphere or other fluid medium, and
by the action of which medium on the last-mentioned piston the backward or
reverse stroke of the steam piston is effected. In applying the machinery
to propelling vessels on water, the cylinders may be placed horizontally, and
the open end of the second cylinder passed through the stern of the vessel
below the water, which then serves as the fluid medium to produce the return
stroke of the pistons, and also serves as the resistance for the propelling action
of the piston of the open cylinder. A similar arrangement may be placed at
the bows of the vessel, for causing it to move astern when required. A similar
arrangement is applicable for propelling on laud, the atmospheric air supplying
the place of the water.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Thomas Scott in the Great Seal Patent Office on the 3rd
October 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, THOMAS
SCOTT, of Brighton, in the County of Sussex, Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Third day of April, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto me, the
said Thomas Scott, Her special licence that I, the said Thomas Scott, my
executors, administrators, and assigns, or such others as I, the said Thomas
Scott, my executors, administrators, and assigns, should at any time agree
with, and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise, and
vend, within the United Kingdom of Great Britain and Ireland, the Channel
Islands, and Isle of Man, an Invention for "IMPROVEMENTS IN MACHINERY
FOR PROPELLING," upon the condition (amongst others) that I, the said Thomas
Scott, by an instrument in writing under my hand and seal, should particularly
describe and ascertain the nature of the said Invention, and in what manner
the same was to be performed, and cause the same to be filed in the Great
Seal Patent Office within six calendar months next and immediately after the
date of the said Letters Patent.
NOW KNOW YE, that I, the said Thomas Scott, do hereby declare the
nature of the said Invention, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
thereof, reference being had to the accompanying Drawing, and to the
figures and letters marked thereon, that is to say :-
I employ a steam cylinder and a piston, which is connected with another
piston fitted to and working in another cylinder of larger diameter, one side of
which latter piston is exposed to the atmosphere or other fluid medium, and
by the action of which medium on the last-mentioned piston the backward or
reverse stroke of the steam piston is effected. In applying the machinery to
propelling vessels on water, the cylinders may be placed horizontally, and the
open end of the second cylinder passed through the stern of the vessel below
the water, which then serves as the fluid medium to produce the return stroke
of the pistons, and also serves as the resistance for the propelling action of the
piston of the open cylinder. A similar arrangement may be placed at the
bows of the vessel, for causing it to move astern when required. A similar

page_text: arrangement is applicable for propelling on land, the atmospheric air supplying
the place of the water.
Figure 1 of the accompanying Drawing is a vertical longitudinal section of
a portion of the stern of a ship with my improved propelling machinery.
A, A, are two steam cylinders fitted with pistons B, B, whose rods C, C, are
attached to other pistons D, D, working in the larger cylinders E, E. The
after ends of the cylinders E, E, are fixed in the stern of the ship in a water-
tight manner, and are open to the water. F, F, are two slide valves which
alternately open a communication from each steam cylinder to its valve box G,
and to the eduction passage H. I is the steam pipe which supplies the valve
boxes G, G. K is a pipe which conveys the eduction steam from the passages
H, H, to the condenser, or to the atmosphere when the condenser is not
employed. The adjoining ends of the cylinders A and E communicate
together, and may be put in connection with the condenser, or with the
atmosphere, or with an air pump.
The two valves F, F, are attached to the same rod, which is worked by a
lever L.
The action of the machinery is as follows:-The valves being placed in the
position shewn in Figure 1, steam enters into the upper cylinder A, and forces
its piston B, together with the corresponding piston D, to the opposite ends of
their respective cylinders. The column of water contained in the upper
cylinder E is thus forcibly expelled, and the ship is driven forwards; at the
same time the lower cylinder A is put in communication with the condenser
by means of its valve F. The space between the pistons B and D, being
permanently in connection with the condenser, the piston B will be in
equilibrium, and the return stroke will be effected by the pressure of the
atmosphere and the column of water acting on one side of the piston D
against the vacuum on the other side. Or the space between the pistons
B and D may be in communication with the atmosphere, in which case the
return stroke is effected by the column of water acting on the large piston D,
and the pressure of the atmosphere acting on one side of the small piston B
against the vacuum on the other side. When no condenser is employed, and
the
space between the pistons is open to the atmosphere, the return stroke may
be effected by the pressure of the column of water on the large piston D. By
partially exhausting the space between the pistons B and D by means of an
air pump, the return stroke may be effected by means of the column of water
acting on the large piston D, and the pressure of the atmosphere acting on the
difference of the areas of the pistons B and D.
Whichever arrangement is adopted, the lower pistons B and D will make

page_text: their return stroke while the upper ones are making their outward or propelling
stroke. The lower cylinder E at the same time fills with water. The valves
F, F, are now raised by the lever L, when the lower pistons will make their
outward or propelling strokes, and the upper pistons will make their return
strokes. This alternate action being kept up, the ship is propelled forward.
Two pairs of these propelling and steam cylinders may be placed in the ship
one on each side of the keel and stern post, as shewn in Figure 2, which is a
plan, and in Figure 3, which is an end view of the same. Figure 4 is a
transverse section of the vessel. The same letters indicate similar parts in
each Figure. The air pump may be worked by a separate steam engine, which
may also work the valve lever L, and the pumps for supplying the boiler with
water. The valves may also be worked by tappets or rods within the steam
cylinders A, or within the propelling cylinders E, and acted on by the pistons
B and D, or their rods C. These rods or tappets must be fitted in the cylinders
by means of stuffing boxes or otherwise, so as to prevent the escape of steam
or water, or the entrance of air, as the case may-be. A similar apparatus may
be fixed in the bows of the ship for the purpose of propelling it astern.
By mounting the whole apparatus upon a carriage, in lieu of fixing it in a
ship, it becomes adapted for propelling on land. The fluid medium in this
case is the atmospheric air in lieu of water.
Having now described the nature of the said Invention, and in what manner
the same is to be performed, I wish it to be understood that what I claim is,
the construction of machinery for propelling by means of a steam cylinder
and piston, connected directly with a propelling cylinder and piston of larger
diameter, as herein-before described, and so arranged, that the outward or
propelling stroke may be produced by the pressure of the steam, while the
return stroke is effected by the pressure of the atmosphere or other fluid
medium, in manner herein-before described.
In witness whereof, I, the said Thomas Scott, have hereunto set my hand
and seal, this Thirtieth day of September, in the year of our Lord One
thousand eight hundred and fifty-four.
Witness,
THOMAS LAINSON,
4, Lansdown Terrace, West,
Hove, Brighton, Sussex.
THO. SCOTT. (L.S.)