Generating Steam to the Boilers of Steam-Engines. 339 
the end of it there is an apparatus f attached, by which the 
pressure is indicated ; g, is the feeding or injecting pipe leading 
from the forcing pump h, which may be worked by a connection 
to the moving part of the engine. 
44 In order to generate steam, the vessel a must be filled 
with water, or other fluid or fluids, from the pump h, and 
heated by a furnace, or otherwise ; the steam, or escape-valve 
h, being loaded by means of a weight, with a pressure greater 
than the expansive force of the steam, to be generated from 
such water, or other fluid or fluids, at the time of its generation. 
When the water, or other fluid or fluids, in the generator, has 
attained the necessary degree of heat, say from 400 to 500 de- 
grees of Fahrenheit, more or less, an additional quantity of 
water, or other fluid or fluids, is pumped into the generator, suf- 
ficient to force out a portion of that already heated in the ge- 
nerator from under the weighted-valve 5, into the steam-pipe d, 
where it instantly becomes steam. 
44 An enlarged representation of the valve, and its seat, is 
shewn in the section. Fig. 3. The valve is a spherical bulb, 
falling into a concave seat, in the lower part of the square 
chamber ; the upper part of the valve is a cylindrical rod, 
upon the top of which the weight of the pressing-lever is exert- 
ed ; the lower part of tlje valve is a triangular stem, sliding 
up and down in the cylindrical passage. When the additional 
quantity of water is injected into the generator, by means of the 
force-pump as described, the bulb of the valve rises from its 
seat, and a corresponding quantity of heated water passes up 
between the cylindrical passage and the sides of the triangular 
stem, into the square chamber, where the pressure, no longer 
operating upon that portion of the water, it immediately becomes 
steam, and passes forward through the steam-pipe to the work- 
ing cylinder. 
44 In order that the operations may be renewed, and con- 
tinued regularly, I make use of an adjusting weight on the 
handle of the pump i, which is a small single-stroke forcing- 
pump, with a weight performing the office of an air-vessel. At 
the end of the pump-handle is a chain m, which I connect with 
a simple crank movement, and thus, by a corresponding adjust- 
ment between the weighted steam, or escape-valve b, the throttle- 
