334 



DR A. CRUM BROWN ON THE CLASSIFICATION OF 



-* 



the original and ingenious speculations of Kekule on the constitution of the 

 aromatic bodies should be experimentally confirmed, phenylic alcohol would be 

 an example of the first form (C 5 H 5 )'"$.* The second and third form may be sub- 

 divided into genera, having the generic radicals (R'&)". As we have seen, by far 

 the most important of these is that containing Ho, and it maybe convenient to ex- 

 press this by a separate symbol, say ". Under this genus we have two forms, R"0 

 and R' 2 0. The so-called ketones of the dibasic carbon acids (dicarbonsiiuren) may 

 be regarded as the aldehydes of unknown alcohols of the first form ; thus succinone 



© 



© 



may be considered as the aldehyde of the 

 unknown alcohol, ..... 





©0 



To the second form R' 2 0, belong the greater number of known alcohols, and 

 a considerable number of bodies possessing alcoholic properties, though not 

 generally classified with the alcohols. They form aldehydes or acetones by oxi- 

 dation ; and this reaction is not confined to those substances to which the 

 name alcohol is commonly applied : for instance, mesoxalic acid is the aldehyde 

 (or acetone) of tartronic acid, alloxan that of dialuric acid, gryoxylic acid 

 that of gly collie acid. Confining our attention to those substances of the form 

 R/ 2 e, in which R is of the form {CJI 2n+1 )', and has its C atoms arranged in 



the simplest way (-0-0-0-, &c), we may form the following series of 



sub-generic radicals H©, CH 3 0, C 2 H 5 ©, &c. The first of these we have seen to be 

 the radical of the " true" alcohols, and it seems probable that the second is that 

 of the hydrates of the defines. The arguments in favour of this view (which 

 undoubtedly requires and admits of further experimental research) may be 

 stated thus : — The first member of the series, the hydrate of ethylene, is identical 



with common alcohol, and has the formula ^^i 



n ifu 



The 



* Translating Kekule's graphic formula for phenylic alcohol into the system used in this 



paper, we have 



in which we have the triatomic radical C(HO) united to the tria- 



tomic radical C 5 H 5 . 



f Using the symbol ( ho )— as a contraction for (h)_(o)— . 



