AN IMPROVED METHOD OF GENERATING STEAM
Year: 1824

page_text: MCCURDY'S SPECIFICATION.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
M CURDY, of New York, in the United States of America, but now of Snow
Hill, in the City of London, Esquire, send greeting.
WHEREAS His most Excellent Majesty King George the Fourth, did, by
His Letters Patent under the Great Seal of His United Kingdom, bearing date
at Westminster, the Fifteenth day of June, 1824, give and grant unto me, the
said John McCurdy, my exors, adiiors, and assigns, His especial licence, full
power, sole privilege and authority, that I, the said John M. Curdy, my exors,
adiñors, and assigns, during the term of years therein mentioned, should and
lawfully might make, use, exercise, and vend, within England, Wales, and
the Town of Berwick upon Tweed, and also in all His Majesty's Colonies
and Plantations abroad, the Invention of "AN IMPROVED METHOD OF GENERATING
STEAM," being a communication made to me by a certain foreigner residing
abroad; in which said Letters Patent there is contained a proviso that if I,
the said John M. Curdy, shall not particularly describe and ascertain the nature
of the 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
inrolled 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, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said John
McCurdy, do hereby declare that the nature of the said Invention, and the
manner in which the same is to be performed, are particularly described and
ascertained in and by the following description thereof (that is to say):
pur-
The said Invention of "An Improved Method of Generating Steam," to be
applied to steam engines for propelling boats, machinery, &c. For this
pose the ordinary boilers in use of every description (either partially or wholly
filled with water, and under pressure) are dispensed with; and I declare the
improvements to consist, first, in substituting (instead of boilers) one or more
vessels, which I have thought proper to term "tubular steam chambers," and
which, when heated in a furnace, will convert a given quantity of water
(according to the number of chambers) direct from the reservoir that supplies
the forcing pump, instantaneously into steam, in sufficient quantity to drive the
engine, without the intermediate process of boiling. Secondly, for equalizing
the distribution of the water thro' every part of the interior surface of the
steam chambers; and, thirdly, for charging or loading the steam chambers
with a head or pressure of steam previously to starting the engine. The
steam chambers should be constructed of a convenient length, from six to
twelve feet, of small diameter, say from five to ten inches, and of sufficient
strength (of wrought or cast iron or other material) to resist, when heated, any
required pressure of steam. Heads are attached to one end of the steam
chambers, into each of which a small tube is inserted, of about one inch in
diameter (which are perforated in every part with small holes), and which
tubes are termed "injection barrels," extending through the centre of the
steam chambers, and connected by means of pipes with the forcing pump.
To the other end of the steam chambers, connected by a pipe, is affixed the
safety valve, and also the eduction tube for admitting the steam upon the
engine. The steam chambers are now set in a furnace, and heated to any
required degree of temperature. They are then loaded or charged with steam
by injecting water into them by means of a forcing pump (which may be an
extra one, and worked by hand); the water passes from the reservoir into the
injection barrels, and from thence is forced and distributed in small sprees or
streams against the interior surface of the steam chambers, the heat of which
instantaneously converts it into steam. As soon as the steam chambers are
charged with steam to a sufficient heighth, which is ascertained by the safety
valve, it is gradually admitted upon the engine in the usual manner, by means
of a cock or valve. As soon as the engine starts, every successive stroke of
the forcing pump attached to it will inject into the steam chambers an addi-
tional supply of water, and by this means the steam will be constantly kept

page_text: up. They may be used for high or low pressure engines; power may be
encreased to any extent by encreasing the number of steam chambers, also by
encreasing the heat of the furnace and the quantity of water injected; each
steam chamber, with about an half gill of water injected at every stroke of
the forcing pump, is considered about equal to a four or five horse power.
The position of the steam chambers in the furnace may be varied; their shape
may be straight or with an elbow; the orifice or bore may be uniform or
tapering. Each one may have stop cocks to disconnect it from the rest, so as
not to stop the engine in case of an accident to any particular one. A cock
may also be inserted in the lower side of the steam chambers, to ascertain if
the forcing pump injects a greater quantity of water than the chambers are
capable of converting into steam. I claim exclusive privilege for the following
improvements:-First, for converting water, either warm or cold, (direct from
the reservoir that supplies the forcing pump,) instantaneously into steam of any
required pressure, and in sufficient quantities to drive the engine without the
use of any boiler under pressure. Secondly, the mode or method of distributing
the water through every part of the steam chambers, so as to diminish as little
as practicable the action of the fire upon the steam chambers. Thirdly, for
creating a head of steam by charging the steam chambers previous to starting,
and without the use of the engine. The prominent advantages of the steam
chambers are, saving in expence of first cost, saving in weight, room, and fuel,
exemption from danger, their simplicity, strength, and durability.
In witness whereof, I, the said John McCurdy, have hereunto set my
hand and seal, this Seventeenth day of June, in the year of our Lord
One thousand night hundred and tronte Cous
JN° MCCURDY. (LS.)
AND BE IT REMEMBERED, that on the Seventeenth day of June, in the
year of our Lord 1824, the aforesaid John MoCurdy came before our said
Lord the King in His Chancery, and acknowledged the Specification afore-
said, and all and everything therein contained and specified, in form above
written. And also the Specification aforesaid was stamped according to the
tenor of the Statute made for that purpose.
Inrolled the Eleventh day of December, in the year of our. Lord One
thousand eight hundred and twenty-four.