48 Dr. T. Thomson on Pyroxylic Spirit afid its Compounds. 



pyroxylic spirit is used, the compound is C^ H^ O, or it con- 

 tains an atom of olefiant gas less than aether. This is the 

 same thing in both cases as abstracting one half of the water 

 which the spirit contained. But in reality 



Alcohol is C*H^O + HO 



While this gas is C^ W + H O 

 We see the reason why its properties are so different from 

 those of alcohol. 



Action of the hydr acids on pyroxylic spirit. — When pyroxy- 

 lic spirit is made to acton the hydracids, a set of compounds 

 is formed very analogous to the aethers which the same acids 

 form with alcohol. These bodies have been examined by 

 Dumas and Peligot, who consider them as compounds of the 

 hydracid employed and methylene, which in their opinion 

 acts the part of a base*. 



1. Chloride or muriate of methylene. — This compound, 



* Dumas and Peligot have given the methylene to what they consider to be 

 the base of pyroxylic spirit, and which they make C" H^'', and pyroxylic spirit 

 they make C'^ H- + H O, But the subject will be much simplified if we 

 apply Liebig's theory of aethers to pyroxylic spirit, with the requisite mo- 

 dification. The base of pyroxylic spirit will be O- H^, and pyroxylic spirit 

 will be C- H^ O. This base has not yet been insulated, but the following 

 salts are obviously the chloride and iodide of C^ H^, which we may, after 

 Dumas and Peligot, denominate methylene. 



It follows from the experiments of Dumas and Peligot, that pyroxylic 

 spirit is C H'' O. Perhaps it would be better to double these numbers, 

 and to consider it as C^ H^ O + H O. It would then bear the same rela- 

 tion to the base which these chemists have distinguished by the name of 

 methylene, that alcohol does to a;ther. On that view we might consider 

 the unknown basis of pyroxylic spirit to be C^ H^, or methyl. Of this pyr- 

 oxylic spirit is the hydrated oxide. The other compounds, by Dumas and 

 Peligot's analysis, are 



Chloride or muriate of methylene . . C^ H^* + Chl^ 



Iodide or hydriodate C" H-'' + lod 



Fluoride or fluate C- PP + Fl 



The salts of methylene, analogous to the acid aethers, are the following : 



Sulphate C-H^O+SO'' 



Nitrate C' H^ O -f Az O^ 



Oxalate C^ H^ O +0^03 



Acetate C^ H^ O + C H^ O^ 



Formate C^ IP O + C- H O^ 



Benzoate C^ II'' O -\ C'^H^O-* 



Mucate C^H^O + €« IP O? 



Oxychlorocarbonate C^ H^ O + C^ Chi 0=» 



Chlorocyanate C^ H^ O + (C^ Az) Chi 



Cyanate C" H^* O + 2(0^ AzO) + 3(H0) 



The acidulous methylene salts, similar to althionic acid, and the other 

 compound ajthereal salts, are the following : — 



Sulphomethylic acid C^ H-' O + 2 (S O^) 



Tartromethylic C-' H^ O + 2 (C H" O^) 



Raceraomethylic C^ H^ O + ^ (C^ H^ 0*) 



