A NEW METHOD OF RAISING WATER AND OTHER FLUIDS FOR THE PURPOSE OF DRIVING MILLS AND OTHER MACHINES AND WATER- ING LANDS, ALSO FOR DRAINING LANDS, AND PUMPING OR CLEARING WATER FROM SHIPS, AND FOR EXTINGUISHING FIRES IN HOUSES, AND OTHER USEFUL PURPOSES, WHICH I APPREHEND WILL BE OF GOOD PUBLICK UTILITY
Year: 1787

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, 1, THOMAS
MITCHELL, Writer, of Perth, in North Britain, send greeting.
WHEREAS His most Excellent Majesty King George the Third, by His
Royal Letters Patent under the Great Seal of Great Britain, bearing date at
Westminster, the Twenty-eight day of August last, upon the petition of me,
the said Thomas Mitchell, did give and grant unto me, my executors, adiñiors,
and assigns, His especial license, full power, and sole privilege and authority,
that I and they, and every of us, by myself and themselves, or by my and
their deputy & deputies, servants or agents, or such others as I or mine
aforesaid shall agree with, and no others, from time to time and at all times
thereafter during the term of years therein expressed, shall and lawfully may
make, use, exercise, and vend, within that part of His Majesty's Kingdom of
Great Britain called England, Dominion of Wales, and Town of Berwick-
upon-Tweed, an Invention of "A NEW METHOD OF RAISING WATER AND OTHER
FLUIDS FOR THE PURPOSE OF DRIVING MILLS AND OTHER MACHINES AND WATER-
ING LANDS, ALSO FOR DRAINING LANDS, AND PUMPING OR CLEARING WATER FROM
SHIPS, AND FOR EXTINGUISHING FIRES IN HOUSES, AND OTHER USEFUL PURPOSES,
WHICH I APPREHEND WILL BE OF GOOD PUBLICK UTILITY," in such manner as to me or
mine aforesaid, or any of us, shall seem meet, and that I or mine aforesaid shall
& lawfully may have and enjoy the whole profit, benefit, commodity, and
advantage from time to time coming and arising by reason of the said Inven-
tion, for the term of years therein mentioned; and it is by the said Letters
Patent declared and provided, that if I 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, & cause the
-

page_text: same to be inrolled in His Majesty's High Court of Chancery, within one
calendar month 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 and become void; and it is farther provided by the said
Letters Patent, that the same shall be valid in my favour, notwithstanding
the not full and certain describing the nature and quality of the said Inven-
tion, or the materials thereto conducing & belonging, as in and by the said
Letters Patent, to which I refer, it doth more fully appear.
NOW KNOW YE, that in compliance with the proviso as to the time
and description contained in the said Letters Patent, I, the said Thomas
Mitchell, do hereby declare that my said Invention for raising water and
other fluids consists in these things:-
First, to rarify the air with fire or ignited substances in a close vessel above
water or other fluids, and above a conducting pipe or tube placed between them,
with a valve at the upper end of the tube opening into the air vessel, whither
the atmosphere will press and rush up the fluid, and where it will stand till
it be discharged for any useful purpose, in the manner after mentioned.
This may be called a fire pump. But in explanation of this:-Take a vessel
or cistern of any matter, form, or size, fit for the purpose; but, for an example,
suppose it to be of copper, and cylindrical, nine feet long and six feet in
diameter; to have an arched roof or cover, with one or more openings in it, and
lids on them, as may be found convenient or necessary; and in the middle to
have an neck or tube of copper, open, and about a foot and half in diameter
and one foot deep, to be placed with one half above the cover, and the other
half below it; a collar of leather on each side of the neck, with a hole in each of
them, and brims around the holes for holding water to make the holes air-tight
when filled with rods, as after mentioned; an opening with a cock, or with a
pipe and valve ending in a cistern of water, to cover the valve and make it air-
tight; this cock or pipe to be one foot in diameter, and that much or more
in length, made of brass, copper, or other metal; then a tube or pipe of
proper matter, form, and size; but suppose it of copper and cylindrical, twenty
feet long, and one foot in diameter, having a valve in the upper end of it; join this
valved end into the bottom of the said vessel or cistern at the middle; erect the
machine with the nether end of the long tube in water or other fluids, then
let down fire or ignited matter by the hand or machinery, through the said
neck into the said cistern, perhaps to two thirds of the depth; hold it then
about six seconds of time, in order to burn or rarify the air in the vessel; then
pull up the fire suddenly into the neck for other six seconds. The effect pro-
posed is to be this-the atmosphere will press or rush up the water or other

page_text: fluid into the vessel or cistern, and compress the rarified air into half or a less
space of the vessel, and fill the vessel so far with the fluid itself; the fluid will
stand there till it be discharged by the opening the lids in the top and the cock
at the bottom, and allowing it to pass away for any useful
purpose into a dam
or otherwise. The vessel will be emptied probably in ten seconds, and the
operation may be performed by one man twice in a minute. The machinery
for managing the fire may be of any convenient sort, subordinate or subservient
to the principle and effect proposed; but suppose two iron rods, about an inch
diameter, and sufficiently long to move in the holes of the collars of the
leather in the cover of the vessel, joined together at the nether and upper ends
by iron bars; and on the nether bar to be fixed a proper piston of metal,
leathered round the edge, with a fireplace on it in the form of
drawn glass;
then fire to be put into this, and the frame let down with it; when it is
raised up the piston is to fill and close the neck. By this machine, eight, ten,
or more tons of water may be raised in a minute, and it may be used at the
sides of the sea, of lakes and rivers, for the purposes mentioned in the
foreside Letters Patent, and others, to public utility. And, if found necessary,
another machine of the same sort may be set up, and wrought with the one
above described, to raise more water and produce a more continued stream;
also, by condensing the air by a condenser or syringer in a separate vessel, and
rarifying such air by fire and stone, and then letting it in by a conducting
pipe and cock upon the surface of the water raised into the said fire pump,
this water may be thereby projected or jetted to another useful heighth, through
a pipe added to the one at the bottom of the vessel. For further explanation
a Sketch or Drawing of these machines is add on the margin.
Secondly, my Invention goes to raise and discharge, by a hand pump, a
much greater quantity of water, with less fricton and more ease, in the same
time and with the same power, than is commonly done. In explaining this: —
Take the barrel of a hand pump, of any matter, form, or size fit for the purpose,
but suppose it, for an example, to be of metal and cylindrical, three feet long, and
eighteen inches in diameter, having a valve in the top of it, and perhaps one
at the bottom, a cock or pipe with a valve at the end of it, in a cistern of
water, to cover the valves, and this to be nine inches in diameter, and of a
convenient length, placed in the side and near to the bottom of the barrel,
two covers to be put upon the upper end of the barrel, near to each other, the
undermost to be as solid as may be necessary, and the uppermost to have a
collar of leather around the opening for a piston, with brims for holding water
to keep this opening air-tight when filled with the piston; and let there be a
cock through the covers for letting air in and out, according to necessity or

page_text: convenience in the operation; hang a solid piston without a valve through
the covers into the barrel; let it be three feet long and nine inches in
diameter, having the nether end of it terminating in a conical or pyramidal
form; let the piston reach down no farther in working than to the half of
the barrel; let there be handle to the piston, and a lever at the upper end of
it, with a man to work the pump when it is erected in and above water or
other fluid. The effect proposed is to raise and discharge much more water,
with less friction, in the same time and by the same power, than has hitherto
been done; and if a pipe be added to the discharging cock or pipe of the
barrel the water or other fluid may be farther raised or jetted to another
height. The piston of this pump is to be varied, or made larger or less heavy
or light, to answer the bore of the pipe below the barrel, the intended height of
the water, and the efficacy of the work. And this pump may be applied to
the uses mentioned concerning the fire pump above described. A figure or
sketch of it is given in the margin.
Lastly, my Invention goes to raise water or other fluids by air condensed by
water on a proper vessel, and let in upon the surface of the water to be
raised from another vessel. To explain this:-Take a vessel of any matter,
form, or size, sufficiently strong and air-tight, but suppose it of metal, and
oblong, twenty feet long, twelve feet broad, and three feet deep, having an
opening in the bottom, and a valve thereon, perhaps eighteen inches in
diameter; place the vessel in the sea at low-water mark when the tide is to
rise, place another vessel of the same size and form when the tide may cover
it at high water; let there be a pipe of communication, with a cock therein.
from the lower vessel to the higher, and a pipe of projection or set from the
higher vessel. The effect proposed is this:-The rise of the tide will condense
the air in the lower vessel to the half or third of the space, and this air, let
out upon the surface of the water in the upper vessel, will force it out to a
height equal to the rise of the tide. The same thing is to be done by the fall
of water from a fountain into a vessel below it, so as to raise the water at the
fountain to a height above it equal at least to the length of the fall. For
farther explanation, a Figure or Drawing of this is added on the margin.
In witness whereof, I, the said Thomas Mitchell, have hereunto set my
hand and seal, this Twenty-sixth day of September, in the twenty-
seventh year of the reign of our Sovereign Lord George the Third, by
the Grace of God King of Great Britain, France, and Ireland, De-
fender of the Faith, and in the year of our Lord One thousand seven
hundred and eighty-seven.
THO. (L.S.) MITCHELL.

page_text: AND BE IT REMEMBERED, that on the Twenty-seventh day of September,
in the year of our Lord 1787, the aforesaid Thomas Mitchell 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
5 above written. And also the Specification aforesaid was stampt according
to the tenor of the Statutes made for that purpose.