IMPROVEMENTS IN OBTAINING MOTIVE POWER BY THE AID OF ATMOSPHERIC AIR, AND IN OBTAINING COMBUSTION
Year: 1848

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
HOUSTON, of Stepney, in the County of Middlesex, Surgeon, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her Royal
Letters Patent under the Great Seal of the United Kingdom of Great Britain and
Ireland, bearing late at Westminster, the Eighth day of March, One thousand
eight hundred and forty-eight, in the eleventh year of Her reign, did, for Herself,
Her heirs and successors, give and grant unto me, the said John Houston, my
exors, adiñors, and assigns, Her especial licence, full power, sole privilege and
authority, that I, the said John Houston, my exors, admňors, and assigns, or
such others as I, the said John Houston, my exors, admors, or assigns, should
at any time agree with, and no others, from time to time and at all times
during the term of years therein expressed, should and lawfully might inake,
use, exercise, and vend, within England, Wales, and the Town of Berwick-
upon-Tweed, in the Islands of Jersey, Guernsey, Alderney, Sark, and Man,
and also in all Her said Majesty's Colonies and Plantations abroad, my
Invention of "IMPROVEMENTS IN OBTAINING MOTIVE POWER BY THE AID OF
ATMOSPHERIC AIR, AND IN OBTAINING COMBUSTION;" in which said Letters Patent
is contained a proviso that I, the said John Houston, should cause a
particular description of the nature of my said Invention, and in what
imanner the same is to be performed, by an instrument in writing under
my hand and seal, to be inrolled in Her Majesty's High Court of Chancery
within six calendar months next and immediately after the date of the said
in part recited Letters Patent, as in and by the same, reference being thereunto
had, will more fully and at large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, 1, the said
John Houston, do hereby declare, that the nature of my said Invention, and
the manner in which the same is to be performed, are fully described and
ascertained in and by the following statement thereof, that is to say:-
My Invention consists of improvements in engines worked by atmospheric
air, and in employing the heated air coming from such engine to aid in the
combustion of the fuel used in the furnace of a steam boiler.
And in order that my Invention may be most fully understood and readily
carried into effect, I will proceed to describe the means pursued by me; and in
doing so I would first remark, that various efforts have heretofore been made to
obtain power by applying heat to atmospheric air when in a state of compression,
and then using the compressed heated air to act on a piston of an engine in like
manner to that in which steam is employed. I do not therefore claim the use of
heated compressed atmospheric air as a means of obtaining power generally,
but only when a supply of atmospheric air is kept up and heated as hereafter
explained. And the peculiarity of an air engine constructed according to my
Invention consists of causing a constant supply and compression of atmo-
spheric air to be taking place by the working of a steam engine, then causing
the compressed air to become heated by passing through tubes or heating
apparatus contained in the steam boiler of the steam engine, then causing the
heated compressed air to act on a piston of an engine in like manner to
steam, and afterwards either to pass into the atmosphere, or, what I prefer,
into a closed ash-pit of the boiler furnace, or at the bridge, or over the fuel
of the furnace, to be the means, or partly the means, of combustion of the
fuel employed for generating steam in the boiler. By this mode of con-
structing and working an air engine, the heated and compressed air may be
kept more uniform and regular in temperature and pressure than by any of
the means heretofore resorted to, and a more highly beneficial result obtained
than has heretofore been accomplished when using heated compressed air as
a means of obtaining motive power. In carrying out my Invention, I employ
a high-pressure steam engine, of comparatively small power as compared to
the power obtained thereby, and I prefer to use steam of about one hundred
pounds on the square inch, though I do not confine myself thereto, and the
power of the steam engine is only used as a means of keeping up a constant
supply of atmospheric air, in proportion to the rate at which the atmospheric
air is to be used in working the air cylinder of the engine. The air pump or
pumps put in motion by the steam engine, I construct of such a capacity as
to force a quantity of atmospheric air, equal to the measure of steam con-
sumed by the steam engine, and I make the air working. cylinder of about

page_text: twice the capacity of the steam cylinder; and I so arrange the valves or slides,
as is well understood, as to cut off the incoming heated compressed air at any
part of the stroke, so as to enable me to regulate the consumption of air to
the quantity pumped into the apparatus hereafter described, intermediate of
the pump or pumps and the air working cylinder, by which means the highly
compressed and heated air enters the working cylinder in a highly expandable
condition, and will move the piston for a distance with the full force thereof,
and then being cut off, it will expand and complete the stroke by the pressure
of expansion, and, being heated, will at the end of the stroke pass into the
atmosphere in the manner of high pressure-steam; or, what is more advan-
tageous, I use it to improve the combustion of the fuel in the furnace of the
steam engine boiler, for which purpose cause it to be conveyed by a pipe
into a closed ash-pit, or it may be introduced at the bridge or other convenient
part of the furnace, in order to ignite the black uninflamed products of the
coal, in like manner to what heated air has before been introduced into
closed ash-pits, or over the fire, or at the bridge of a furnace. And which
means of using heated air is not in itself new, and therefore use of heated
air is not claimed by me separately, and is only new when conjoined with
an air engine constructed and worked according to my Invention. The air
from the pump or pumps actuated by the steam engine I cause to pass into
a strong reservoir or vessel previously full of atmospheric air in a compressed
state, and I prefer the compression to be about one hundred pounds on
the square inch, but do not confine myself thereto, and this vessel is to be
provided with a safety valve weighted to the pressure mentioned; and the
size of such reservoir or vessel which I have used is about thirty to thirty-
five times the capacity of the air pump or pumps used; the object is to have
such a quantity of compressed air in store, that any slight variation of the
supply of air thereto, or in the use by the air working cylinder, may not
materially prejudice the uniform working of the engine. The compressed air
from the reservoir is passed either directly to the heating apparatus contained
in the steam boiler, or, in its progress there, it may pass through a pipe acted
on by the fire of the furnace, in which case the pipe used is to be of copper,
and inded I prefer the apparatus in the boiler for heating the air to consist of
copper, as being the best conductor of heat. It is important to the well
working of this engine that the air should be retained sufficiently long to be
acted on by heat, that it shall, before passing to the air working cylinder,
have become as highly heated as the steam in the boiler; for which purpose
I prefer to make use of numerous tubes or pipes within the boiler, and so to
connect clusters thereof that the compressed air having passed through the

page_text: boiler in one cluster of pipes or tubes, and thereby have become partially
heated, then to pass back through the boiler in another cluster of pipes, and
so on. And in order that there may be at all times several times more air in
the tubes or heating apparatus than will be used in one stroke of the piston
in the air working engine, I make the air heating apparatus in the boiler
as extensive as the steam boiler will admit of, the object being, as before
stated, to obtain a heat to the compressed air equal to that of the steam in
the steam boiler; and, although I prefer to use tubes or pipes for that
purpose, other arrangements of heating apparatus acted on by the water or
steam of the steam boiler may be resorted to.
Having thus described the nature of my Invention, and the manner in
which the same is to be performed, I would remark, that I do not confine
myself to the relative proportions, pressures, or dimensions herein mentioned,
so long as the peculiar character of my Invention is retained. But what
I claim is, the mode herein-before described of constructing engines to be
worked by heated compressed atmospheric air, whereby the steam from a
steam boiler is caused to give motion to a steam engine, in order to keep up
a supply of air in a state of compression, such compressed air being then
heated by means of the steam boiler, and then used to act on the piston of
an engine as herein explained.
In witness whereof, I, the said John Houston, have hereunto set my
hand and seal,-this Eighth day of September, in the year of our Lord
One thousand eight hundred and forty-eight
No text detected.