33P Mr Perkins? Method of applying his New Invention 
valve, (which it is not thought necessary to shew in this drawing) 
and the weight on the handle of the pump i, a certain quantity of 
water is forced into the generator, at every stroke of the pump, 
and a corresponding quantity forced from under the weighted 
valve b, to become steam. 
“ These principles may be modified and applied to the 
boilers of ordinary steam-engines, a mode of adopting which 
is shewn in Fig. 3. The invention is here represented un- 
der another form, and differently employed, being a plan for 
heating the water of an ordinary engine-boiler, with a view, 
principally, to save fuel : z 9 is a tube communicating with the 
ordinary steam-boiler ; a 9 a , is the generator, a cylindrical 
metallic vessel, of which there may be several connected to- 
gether ; these are filled with water as above described, having 
the furnaces y, y, under them ; h is the escape-valve through 
which the heated water passes ; c, is the weighted lever pressing 
down the valve with the required force : d, is the chamber and 
pipe, in which the heated water that escapes through the valve 
becomes steam, and thence passes through the tube z 9 into the 
boiler. This boiler (of a cylindrical form with spherical ends) 
is proposed to be inclosed within a cask or other vessel, and sur- 
rounded with pounded charcoal, which material being a very 
imperfect conductor of heat, is particularly well calculated to 
preserve the heat of the water and steam within the boiler ; e , is 
a pipe leading from the generator, which is also filled with the 
heated water ; and at die lower end of this pipe there is an ap- 
paratus f, for ascertaining the pressure of the fluid within the 
generator. This fluid, by exerting its force at the lower end 
of the pipe e , against the lever connected to a weighing-machine, 
causes the index to point out upon the graduated dial-plate the 
number of atmospheres under which the steam is generated. 
The pipe e , being in substance considerably thinner than any 
other part of the apparatus, is intended to give way, in the 
nvent of the pressure within the generator being accidentally 
raised to a dangerous height ; the consequence of which would 
be, that the pipe e would open, and the steam blow out through 
the fissure, without the possibility of producing any injury ; g, 
is the pipe through which the water is injected by the pump h, 
