548 Scientific Proceedings, Royal Dublin Society. 
The apparatus consists essentially of a strong glass flask about 
300 ce. capacity, having a bulb of about 20 cc. capacity blown on 
its neck ; between the bulb and the flask 
there is a well-ground stop-cock, having 
an aperture of at least 5 mm. in diameter ; 
beyond the bulb the neck terminates in 
a tubulare, having a slightly funnel- 
shaped opening into which is loosely 
fitted a tube passing through a sort of 
Liebig condenser in a vertical position, 
this tube communicates with a Sprengel 
pump. The capacity of the flask with 
the stop-cock turned off is determined, 
this quantity represents the volume of 
water which may be examined. The 
manner in which the apparatus is filled 
must.depend upon circumstances. It is 
obvious that no notable increase of the 
temperature of the water in the flask 
must take place as long as the cock is 
turned off, so that if any considerable 
time must elapse between the filling of 
the flask and the expulsion of the gases 
it is desirable to attach a piece of india- 
rubber tube to the bulb and to fill the 
entire apparatus completely with the 
water, leaving the cock open and tying 
the tube in such a manner as to provide 
for the alteration in volume that may 
result from change of temperature. Since, 
however, the gases dissolved in most 
natural waters are in the presence of 
more or less organic matter of a not very 
stable character, it is useless to attempt 
great accuracy in the determination of 
the gases unless the water can be ex- 
amined within a short time after it is collected, so that the pro- 
vision for expansion will seldom be found necessary. Assuming 
