12 



Professor Apjohn upon a new Method of 

 (3) 



Atmospheric Air ...... 



Azote 



Oxygen, (by calculation) 



Hydrogen 



Carbonic Acid 



Carbonic Oxide. ....... 



Nitrous Oxide 



Upon these results I never placed much reliance. The apparatus employed 

 was very imperfect, particularly in not permitting more than a single experiment 

 on the same quantity of gas ; and I also saw reason to doubt that I had in every 

 instance by means of it accomplished perfect desiccation. Under these circum- 

 stances I always contemplated returning to the subject, and towards the latter 

 end of last July, I did actually commence a fresh series of experiments, which 

 were conducted on the following plan. 



A pair of copper gasometers. A, B, with glass bells, C, D, such as are usually 

 employed by chemical lecturers, were charged with a proper quantity of oil of 



