IMPROVEMENTS IN OBTAINING MOTIVE POWER
Year: 1845

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, DAVID
WILKINSON, of Potters Pury, near Stoney Stratford, Gentleman, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her Royal
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Tenth day of October, in the ninth year of Her reign, did, for
Herself. Her heirs and successors, give and grant unto me, the said David
Wilkinson, my exors, adiñors, and assigns, Her especial licence, full power, sole
privilege and authority, that I, the said David Wilkinson, my exors, adiñors, and
assigns, or such others as I, the said David Wilkinson, my exors, adiiors, 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 make, use, exercise, and vend, within England, Wales, and
the Town of Berwick-upon-Tweed, my Invention of "IMPROVEMENTS IN
OBTAINING MOTIVE POWER;" in which said Letters Patent is contained a pro-
viso that I, the said David Wilkinson, shall cause a particular description of
the nature of my said Invention, and in what manner the same is to be
performed, to be inrolled in Her said 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.
NOW KNOW YE, that in compliance with the said proviso, I, the said
David Wilkinson, do hereby declare that the nature of my said Invention,

page_text: 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 a mode of combining heated air with steam, and
causing them, when combined, to act together in moving the piston of an
engine, in place of employing steam or air alone for that purpose. And in
order that my Invention may be fully understood and readily carried into effect,
I will proceed to describe the means pursued by me; and in doing so I will
suppose that I have a high-pressure steam engine. In order to cause the same
to be worked according to my Invention, I apply an air pump of about half-the-
cubic contents of the cylinder of the engine, but I do not confine myself to
that size, and by means of such air pump I cause atmospheric air to be forced
through tubes or other suitable apparatus externally heated (so that the air
may become highly heated), into a steam boiler or generator or other apparatus,
so that the heated air will combine with the steam and go together into the
working cylinder of the engine, and be the joint means of working the engine;
and although this my Invention is more particularly intended when working
with high-pressure steam, yet it is also advantageous when working by con-
densation. And in applying the Invention to such last-mentioned class of
steam engines, I apply it in the same manner as just described in respect to
high-pressure steam engines.
Having thus described the nature of my Invention, and the manner in which
the same is to be performed, I would remark, that I am aware that it has been
before proposed to cause heated air to pass into a steam boiler, and for such
heated air to act conjointly with steam in working an engine; but in such cases
the air was heated and more or less decomposed by being passed in contact
with the fire by which it was heated, and the air and products of combustion
passed together into the boiler. And I mention this circumstance in order to
state that I make no claim to the use of heated air combined with steam, when
the same has been brought into contact with the fire that heated it, and then
causing it to pass, together with gases and products of combustion, into the
steam boiler.
What I claim is, the forcing of air through pipes or other suitably heated
surfaces, and then mixing the same with steam, and causing the steam and
heated air conjointly to work an engine, as herein described.
In witness whereof, I, the said David Wilkinson, have hereunto set my
hand and seal, this Ninth day of April, in the year of our Lord One
thousand eight hundred and forty-six.
DAVID (L.S.) WILKINSON.

page_text: AND BE IT REMEMBERED, that on the Ninth day of April, in
the year of our Lord 1846, the aforesaid David Wilkinson came before our
said Lady the Queen in Her Chancery, and acknowledged the Specification
aforesaid, and all and every thing 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.
Enrolled the Ninth day of April, in the year of our Lord One thousand
eight hundred and forty-six.