364 Literary and Philosophical Society. 



Absorption of Gases by Charcoal. Part II. On a new 

 Series of Equivalents or Molecules. By R. Angtis 

 Smith, Ph.D., F.R.S. Received January 30, 1879. 



(Abstract.) 



* In the " Transactions of the British Association," 1868, 

 Norwich, on page 64 of the " Abstracts," there is a pre- 

 liminary notice of an investigation into the amount of 

 certain gases absorbed by charcoal. . . . The results given 

 were : — 



Hydrogen ....... i 



Oxygen ....... 7 99 



Carbonic oxide ...... 6 "03 



Carbonic acid ...... 22*05 



Marsh-gas ....... lo-oi 



Nitrous oxide ...... 12 '90 



Sulphurous acid . . . . . • 36'95 



Nitrogen . . . . . . « 4*27 



* It was remarked that the number for nitrogen was 

 probably too low ; I had some belief that the charcoal 

 retained a certain amount which I had not been able to 

 estimate. 



' For common air, the number 40*065 crept into the 

 paper or abstract instead of the quotient 7*06. 



* The cause of this was clear, as I believed, namely, the 

 irregular character of the charcoal with which \ had to 

 deal. The experiments which I had published were for- 

 gotten, I suppose, by most men, but the late Professor 

 Graham told me that he had repeated them with the same 

 results which I had given. I might have considered this 

 sufficient, but waited for time to make a still more elabo- 

 rate investigation of the subject, and to take special care 

 with oxygen, in the belief that, the rule being found, the 

 rest of the inquiry would be easy ; this was extended to 



