PLATE III. 
Apparatus for Extracting Gases from Water. 
A ' flask containing water from which the gases are to be boiled out ; B, gas-bulb, 
terminating in a Jacobsen’s connecting tube with lateral orifice a below, and into a 
condenser-tube c above ; D, jacket of condenser ; E and K, cylindrical gas- 
bulbs communicating through in. The gas aspired goes into E by d, and is driven 
out by f into h, standing in the mercurial trough H. K is the mercury-reservoir, 
its atmosphere can be rarefied by connection with a Bunsen pump through k, 
or condensed by connecting it through n with the copper-ball M, containing com- 
pressed air; P, manometer for M. 
