AN IMPROVEMENT ON STEAM ENGINES
Year: 1817

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
MANWARING, of Mash Place, Lambeth, in the County of Surrey, Engineer,
send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
Letters Patent under the Great Seal of the United Kingdom of Great Britain
and Ireland, bearing date at Westminster, the Twenty-second day of May, in
the fifty-sixth year of His reign, give and grant unto me, the said George
Manwaring, my exors, adññiors, and assigns, His especial licence, full power,
sole privilege and authority, that I, the said George Manwaring, my exors,
adñiors, and assigns, should and lawfully might, during the term of years
therein mentioned, make, use, exercise, and vend, within England, Wales, and the
Town of Berwick-upon-Tweed, my Invention of "AN IMPROVEMENT ON STEAM
ENGINES;" in which said Letters Patent there is contained a proviso that if I,
the said George Manwaring, shall not particularly describe and ascertain the
nature of my said Invention, and in what manner the same is to be performed,
by an instrument in writing under my hand and seal, and cause the same to
be enrolled in His Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said Letters Patent, that
then the said Letters Patent, and all liberties and advantages whatsoever
thereby granted, shall utterly cease; determine, and become void, as in and by
the same, relation being thereunto had, may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
George Manwaring, do hereby declare that the nature of my said Invention,

page_text: and the manner in which the same is to be performed, are particularly
described and ascertained in and by the Drawings hereto annexed, and the
following description thereof (that is to say):---
My said Invention consists in conveying the steam (after leaving the
cylinder in order to be condensed) through a passage or passages surrounded
with water supplied from the hot well. In the passage or passages are fixed
a number of metal pipes or tubes, which are filled with water from the
surrounding casings; the steam in passing striking upon the external parts
of the tubes, imparts a portion of its heat, which increases the temperature
of the water contained in the tubes and surrounding casings in a great degree,
and a constant succession of water passing through the tubes and casings
which is much colder than the steam, causes a greater condensation of it to
take place previous to its reaching the condenser than can be done in the
common way; for the water produced by the condensation of the steam I have
a receiver into which it falls, and is thereby prevented from entering into
the condenser, and to the bottom of the receiver an injection pump is fixed
to force the said water into the boiler of the steam engine, and by thus taking
the water from the receiver, the tubes, and the surrounding casings, I can
supply the boiler with water of a very superior degree of temperature to what
may be done in the common way, and thereby produce a very considerable
saving of fuel employed to work the engine. In the common method the
steam on leaving the cylinder is conveyed through a pipe into the condenser,
and condensed in water, which water is forced by the air pump into the hot
well, from whence the boiler is supplied with water at a very low temperature,
and consequently requires a much greater expence in fuel to convert it into
steam. The means by which I effect this object may be variously contrived
according to the circumstances of the case. I shall describe one method
of doing it, reserving to myself, however, during the term for which my Patent
is granted, the benefits to be derived from the employment of the principle
of my said Invention in whatever mode the same may be applied. The afore-
said manner of carrying my Invention into effect will be explained by the
Drawing hereunto annexed, and the description referring thereto, as follows:-
A, the bottom of the steam engine cylinder; B, the passage for the steam
into and out of the cylinder; C, the lower slide or valve box; D, the
eduction pipe which conveys the steam from the slide or valve box thro' the
refrigerator to the condenser; E, the refrigerator surrounded with water
internally and externally; F, metal tubes which are also filled with water;
G, the passage for the steam amongst the tubes; H, the passage to admit
the steam into the receiver; I, the receiver; K, the pipe which conveys the

page_text: condensed steam to the injection pump; L, the injection pump which forces
the condensed steam into the steam engine boiler; M, the passage for the
uncondensed steam to the condenser; N, the condenser; O, the valve and
passage between the air pump and the condenser; P, the air pump: Q, the
cistern, air-pump head, or hot well; R, the pipe which conveys the con-
densed steam to the refrigerator pump; S, the pump for supplying the
refrigerator; T, T, the pipe to convey the water into the bottom of the
refrigerator; U, the valve for letting off the waste water; V, a cock with
an index to regulate the supply of the water into the refrigerator; W, a
pipe to convey the water from the top of the refrigerator to the boiler;
X, the pipe to convey the water from the injection pump L into the pipe W
to assist in supplying the boiler; Y, the injection valve; Z, the index to
regulate the injection valve. In some cases I may find it convenient to
omit the receiver I, and then the condensed steam passage H, the pipe K,
the injection pump L, and the pipe X will become unnecessary.
In witness whereof, I, the said George Manwaring, have hereunto set
my hand and seal, this Twenty-third day of October, in the year
of our Lord One thousand eight hundred and seventeen.
in the year of our Lord 1817, the aforesaid George Manwaring came before
our said Lord the King in His Chancery, and acknowledged the Specification
aforesaid, and all and every thing therein contained and specified, in form
above written. And also the Indenture aforesaid was stamped according
to the tenor of the Statute made for that purpose.
Inrolled the Twenty-third day of October, in the year of our Lord