| 
} 
Voss 
Hare’s Blowpipe. 299 
gaseous materials may be pumped by a condenser, as in 
the case of Mr. Brooks’ apparatus, used by Clarke. Fig. 
9. A. reservoir, C. bladder holding gas, B. condenser, D 
blowpipe. 
In default of a better mode, two smaller tubs or kegs, or 
air tight boxes inverted into larger ones, might be resorted 
to. Being filled with water, this fluid might be displaced 
by gas delivered from the vessels generating it, and the gas 
thus collected would be propelled by the pressure of the 
water through tubes connected with the compound blow- 
Professor Silliman uses chests sunk in his pneumatic cis- 
tern, and filled by bellows pumps,* as in my original appa- 
now employ sometimes the shelves of my pneu- 
matic cistern, which are made like inverted trays; so that 
bell glasses filled with gas may be emptied into them by 
the hand. 
“Or more frequently by conveying the gases as they are evolved from 
the materials, through tubes immediately into the boxes. 
