254 
M. Lemare has presented to the aca- 
demy an.apparatns, which he calls a 
Calefactor, one that may be very usefully 
employed in domestic economy. The 
eylindrival vessel, placed in the middle, 
is every where surrounded by the fuel 
that heats it, and the fuel is, itself, sur- 
rounded by another vessel in the shape 
of a crown, of the same height as that in 
the middle, and which is filled with 
water. The circular void between these 
two vessels, and which serves as a 
hearth, is pierced at the lower part with 
small holes for the circulation of air. 
New Patents and Mechanical [nventions. 
pOct. 1, 
An indelible ink is becoming more and 
more necessary in proportion to the im- 
proving skill and industry of forgers. A 
manufacturer of Paris, M. de la Renau- 
diére, has presented a sample of ink of 
this description, which combines al! the 
desirable qualitics, and which resists all 
the agents usually employed to efface 
writing. It has received the approba- 
tion of the academy, and the recipe of it 
is placed under seal in the secretary’s 
office, to try whether it will retain its 
qualities; some other kinds, with similar 
pretensions, having failed herein. 
NEW PATENTS AND MECHANICAL INVENTIONS, 
—a—— 
To Jacop Perkins, of Fleet-street, 
London, Engineer; for certain Im- 
provements in Sieam-Engines. Partly 
communicated to him hy a Foreigner 
residing abroad.—Dce. 10, 1822. 
R. Jacos Perkins: declares. the 
nature of his improvements to 
consist in heating water, or other fluid 
or fluids, far the purpose -of generating 
steam for steam-engines, in a vessel or 
vessels kept, during such process. of 
heating, full of such water, or other 
fluid or fluids, and also under pressure ; 
and which said yessel he sometimes 
substitutes for the ordinary boiler used 
in steam-engines, and calls a generator. 
By this arrangement steam is generated 
with a much smaller quantity of fuel 
than by the ordinary boilers used in 
steain-engines of a like power. And 
he also declares that the nature of his 
improvements further consists in cau- 
sine such water, or other fiuid or fluids, 
so heated as aforesaid, to escape from 
under the said pressure, and pass at 
once from the generator into the steam- 
pipe, where it hecomes steam er vapour, 
and in that form may pass thence to the 
cylinder, or to any other situation con- 
nected with a. steam-engine, without 
the necessary intervention of any steam- 
chamber or other reservoir of ‘steam. 
Also, that tbe nature of his improve- 
ments consists in causing such escape of 
water, or other fluid or fluids, to take 
place, by forcing other water, or other 
fluid or fluids. into the generator; and 
thereby maintaining the generator in 
that state of fulness required for the 
parposes of his said invention. Also, 
further consists in the application of the 
hereinbefore declared improvemeits ge- 
nerally, for the purpose of generating 
steam for steam-cngines, whether such 
steam be employed to act through the 
steam-pipe, without a steam-chamber 
immediately on the piston of a steam- 
engine, or to be collected in a reservoir 
or steam-chamber, and thence to act on 
the piston, or for heating the water for 
ordinary steam-engines, or for any other 
purpose for steam-engines. And in 
further compliance with the said pro- 
viso, he does hereby describe a manner 
in which his said invention may be per- 
formed, which manner is the best he 
has hitherto discovered, or is at this 
time in possession of, or informed of, 
and which is ascertained by the follow- 
ing description thereo!.—The said ge- 
herator. may be heated by a variety 
of known furnaces, but the one he has 
used and found to be the best, is one 
of the cupola kind fed by a blast: and 
his safety-pipe, indicator, and forcing- 
pump, are not new, but he claims ex- 
clusive privilege for the following im- 
provements only ; that is to say: 
First, for heating water, or other fluid 
or fluids, for the purpose of generating 
steam for steam-engines, in a vessel or 
vessels kept (during such process of 
heating) full of such water, or other 
fluid or fluids, and under a pressure 
greater than the expansive force of the 
steam to be generated from such water, 
or other flaid or fluids, at the time of its 
generation. 
Secondly, for causing such water, or 
other fluid or fluids, so heated as afore- 
said, to escape from under the said 
pressure, and pass al once from the ge- 
neraior into the steam-pipe, where it 
hecomes steam or vapour, and in that 
form may pass thence to the cylinder, 
or to any other situation connected with 
a steam-cngine, without the necessary 
intervention of any steam-chamber, -or 
other reservoir of steam, 
Thirdly, for the manner of aay 
such 
