322 Dr. A. Smith. Absorption of Gases ly Charcoal. [Feb. B 3 



II. *"' Absorption of Gases by Charcoal. Part II. On a new 

 Series of Equivalents or Molecules." By R. AxGUS Smith, 

 Ph.D.. F.E.S. Received January 30. 1879. 



(Abstract.) 



In the ■"Transactions of the British Association." 1S63. Xorwieh. on 

 page 64 of the "Abstracts." there is a preliminary notice of an in- 

 vestigation into the amount of certain gases absorbed by charcoal. 

 I made the inquiry from a belief previously expressed in a paper 

 of which an abstract is in the •'Proceedings of the Royal Society," 

 page -i25. for 1863. I said in that paper that the action of the gas 

 and charcoal was on the border line between physics and chemistry, 

 and that chemical phenomena were an extension of the physical; 

 also that the gases were absorbed by charcoal in whole volumes, the 

 exceptions in the numbers being supposed to be mistakes. The 

 results given were : — 



Hydrogen .. 1 



Oxygen 7'99 



Carbonic oxide 6 "03 



Carbonic acid 22*05 



Marsh-gas 10"01 ' 



Citrons oxide 12"90 



Sulphurous acid 36'95 



Xitrogen 4" 2 7 



It was remarked that the number for nitrogen was probably too 

 Ioav ; I had some belief that the charcoal retained a certain amount 

 which I had not been able to estimate. 



Tor common air. the number 40'065 crept into the paper or 

 abstract instead of the quotient 7"06. 



I considered the numbers very remarkable, but was afraid that 

 they would be of little interest unless they could be brought more 

 easily under the eyes of others ; my experiments were somewhat 

 laborious ; the exact numbers were seldom approached by the single 

 analysis, but were wholly the result of a series of irregular averages 

 and apparently irregular experiments. The cause of this was clear, 

 as I believed, namely, the irregular character of the charcoal with 

 which I had to deal. The experiments which I had published were 

 forgotten. 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 elaborate investigation of the subject, and to 

 take special care with oxygen, in the belief that, the rule being found. 



