171 
Steam Engine. 
Specification of the patent granted to Mr. Jonathan Horn- 
blower, of Penryn, in the county of Cornwall^ plumhtf 
and hr aster ; for his invention of a machine or engine 
for raising water ^ or other liquids^ and for other pur- 
poses^ by means of fire and steam. 
Dated July 13, 1781.— -Term expired, 1795. 
TO all to whom these presents shall come, he. Now 
KNOW YE, that, in compliance with the said proviso, and 
in pursuance of the said statute, I, the said Jonathan 
Hornblower, do hereby declare, that my said invention is 
described in manner and form following: that is to say, 
first, I use two vessels in which the steam is to act, and 
w'hich, in other steam engines, are generally called cylin- 
ders. Secondly, I employ the steam, after it has acted 
in the first vessel, to operate a second time in the other, by 
permitting it to expand itself, which I do by connecting 
the vessels together, and forming proper channels and 
apertures, whereby the steam shall occasionally go in and 
out of the said vessels. Thirdly, I condense the steam, 
by causing it to pass in contact with metalline surfaces, 
while water is applied to the opposite side. Fourthly, 
to discharge the engine of the water used to condense the 
steam, I suspend a columjn of water in a tube or vessel 
constructed for that purpose on the principles of the ba- 
rometer ; the upper end having open communication with 
the steam- vessels, and the lower end being immersed into 
a vessel of water. Fifthly, to discharge the air which 
enters the steam vessels with the condensing water, or 
otherwise, I introduce it into a separate vessel, whence it 
is protruded by the admission of steam. Sixthly, that 
the condensed vapour shall not remain in the steam ves- 
sel, in which the steam is condensed, I collect it into ano- 
ther vessel, which has open communication with the 
steam vessels, and the water in the mine, reservoir, or 
river. Lastly, in cases where the atmosphere is to be 
