210 yiaws.'R.Yma. on the Combinations of Salicyle. 



and also more perfect means than we now possess of mea- 

 suring the amount of the inductive action; all these circum- 

 stances render the problem very complex. 



[To be continued.] 



XXXVIII. Researches of Mons. R. Piria on the Combina- 

 tions of Salicyle^. 



T^VERY one who is at all acquainted with the gigantic 

 -■-^ strides made in organic chemistry since the discovery of 

 the real nature of the oil of bitter almonds, and the develop- 

 ment of the remarkable combinations of benzoyle, must have 

 hailed with peculiar pleasure the discovery of an analogous 

 series of compounds having for their base a compound radical 

 termed spiroil, from its being present in the oil of the Spiraea 

 Ulmaria, or meadow-sweet. This body was discovered by Lo- 

 wig, who ascertained the volatile oil of the Spiraea to be really 

 an hydracid, consisting ofa compound radical analogous to ben- 

 zoyl, combined with hydrogen. The researches of Lowig have 

 been already presented to the English reader in the pages of 

 the valuable Scientific Memoirs of Mr. R. Taylor. We have 

 now the pleasure of laying before our scientific readers an 

 accountof a valuable series of researches of M. Piria on anew 

 compound organic base, bearing considerable resemblance 

 to benzoyl and spiroil, and promising, from this very resem- 

 blance, to throw much light on the nature of the respective 

 combinations of these curious bases. 



The active principle of the bark of different species of salix 

 has been long known to chemists, and salicin is now an ordi- 

 nary article of commerce, being employed in medicine as a 

 substitute for quinine, as a remedy in intermittent fever. 



Salicine was first obtained in a white crystallizable state, 

 by M. Leroux, and has been submitted to ultimate analysis 

 by MM. Jules Gay-Lussac and Pelouse. Piria has also 

 analysed it, and its per centage composition was in three ex- 

 periments found to be as follows : — 



Exp.]. Exp. 2. Exp. 3. 



Carbon 55-68 55*04 55-54. 



Hydrogen 6*36 6*39 6-4.3 



Oxygen 37-96 38*57 38-03 



100 100 100 



* For this account of M. Piria's researches, the Editors are obliged to 

 Dr. Golding Bird. 



