IMPROVEMENTS IN STEAM ENGINES AND PUMPS
Year: 1867

page_text: LETTERS PATENT to John Garrett Tongue, of the Firm of Tongue and
Birkbeck, Patent Agents and Engineers, of 34, Southampton Buildings,
Chancery Lane, in the County of Middlesex, for the Invention of
"IMPROVEMENTS IN STEAM ENGINES AND PUMPS."A communication from
abroad by Hart Foster Pease, of the City of Brooklyn, in the County of
Kings, and State of New York, United States of America.
Sealed the 30th August 1867, and dated the 6th March 1867.
PROVISIONAL SPECIFICATION left by the said John Garrett Tongue
at the Office of the Commissioners of Patents, with his Petition, on the
6th March 1867.
1. JOHN GARHETT TONGUE, of the Firm of Tongue and Birkbeck, Patent
Agents and Engineers, of 34, Southampton Buildings, Chancery Lane, in the
County of Middlesex, do hereby declare the nature of the said Invention
for IMPROVEMENTS IN STEAM ENGINES AND PUMPS "
The nature of the Invention consists in inclosing a revolving crank and its
operating pitman (which connects with a piston working in a cylinder open at
its one end) within a steam or water tight box, preferably of a form corres
sponding to the travel described by the pitman, whereby a rotary motion may
be obtained through a long connecting rod in a short space or compass, and a
piston rod is dispensed with; also in combination with the foregoing in pivoting

page_text: the pitman to the piston within the body of the latter at or about the middle
of its thickness; to the reduction of lateral pressure or twist upon the piston;
and still further enhancing the compactness of the pump or engine for a given
length of connecting rod.
In applying the Invention to a pump then the main shaft instead of being
rotated by the piston becomes the driver to reciprocate the latter for operation
in concert with suitable valves and suction and discharge pipes connected with
the cylinder.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Garrett Tongue in the Great Seal Patent Office
on the 5th September 1867.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
GARRETT TONGUE, of the Firm of Tongue and Birkbeck, Patent Agents and
Engineers, of 84, Southampton Buildings, Chancery Lane, in the County of
Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of March, in the year of our Lord Oue
thousand eight hundred and sixty-seven, in the thirtieth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the
said John Garrett Tongue, Her special licence that I, the said John Garrett
Tongue, my executors, administrators, and assigns, or such others as I, the
said John Garrett Tongue, 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 STEAM ENGINES AND PUMPS," a communication to me
from abroad by Hart Foster Pease, of the City of Brooklyn, in the County
of Kings, and State of New York, United States of America, upon the
condition (amongst others) that I, the said John Garrett Tongue, my
executors or administrators, by an instrument in writing under my, or their,
or one of their hands and seals, 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:

page_text: contributes to the efficiency of the engine, while the compactness effected is
an important consideration. The chambered head or box H is preferably of a
shape on the inside corresponding to the course of travel described by the
pitman, which reduces the waste of steam in opening the inner end of the
cylinder to the exhaust as compared with a square or other shaped box.
In applying the Invention to a pump then the main shaft instead of being
rotated by the piston becomes the driver to reciprocate the latter for operation
in concert with suitable valves and suction and discharge pipes connected
with the cylinder. .
In the application of the Invention to the steam engine it may here be
observed that the inequality of power which occurs in ordinary reciprocating
piston engines during the two strokes by reason of the piston rod detracting
from the area presented to steam pressure on the piston on its one side. or face
is here avoided, where the crank is made up of a disc with exentric pin, as
shown in the Drawing, then it is important that space should be allowed for
steam to pass in rear of it so as to counteract inside pressure.
Having thus fully described the nature of the Invention, and the manner in
which the same is performed or carried into practice, the novel features and
improvements which it is intended to claim under the above in part recited
Letters Patent are,-
First, the improved combination with the cylinder and its piston of the
steam or water tight box or chambered cylinder head, pitman, and revolving
crank all arranged for operation within said head in open communication
with the cylinder, substantially as herein shown and described.
Secondly, in combination with the above attaching the pitman to the piston
within the body of the latter, essentially as and for the purposes herein
shown and described.
Thirdly, the arrangement of the chambered cylinder bead I constructed
with its internal form corresponding to the course described by the pitman
in its action, substantially as herein shown and described..
In witness whereof, I, the said John Garrett Tongue, have hereunto
set my hand and seal, this Fourth day of September, in the year of
our Lord One thousand eight hundred and sixty-seven.
JOHN G. TONGUE.
(L.S.)