i ‘Hydrostatic Blowpipe. 38 
ait ensues every time that the stroke is repeated’; so that the - 
jower apartment soon becomes teplete with air, which is re- ~ 
tained by the cock until its discharge by the bloWpipe is re- - 
quisite. : 
The cock being opened, the air confined in the lower 
apartment is expelled by the pressure of the water in the u 
per apartment, which, as the air which had displaced it es- 
capes, descends and re-occupies its former situation. The 
piston is worked either by the handle or the treadle, at C. 
In order to supply the cask with oxygen gas, it is only 
necessary to attach to the suction pipe, (by means of the 
gallows and screw at g,) another pipe, duly flexible, and pas- 
sed under a bell containing the gas im question, over the 
pneumatic cistern: er the pipe May communicate with a 
leather bag, filled with oxygen. I have one, which will hold 
ed by rivets, agreeably to 
5s, oF fire- 
that it would be found 
employ the blowpipe in soldering, or in blowing, a mould- 
bes ther- 
¢t, it greatly excels the ordinary blowpipe flame. Be~ 
cides, in this Sen¢ratnent the limits are peculiarly ample, with- 
in which the flame is suseeptible of an instantaneous increase,- 
or diminution, in size, or intensity. _. 3 
I do not believe the heat produced in this way, to be muclr 
more expensive than that produced by a lamp. He at 
f 
=z ? 
