Mons. R. Piria on the Combinations ofSalicyle. £19 

 Decomposition of Salicin hy Sulphuric Acid. 



When salicin is immersed in strong sulphuric acid it as- 

 sumes a blood-red tint ; but when digested at a boiling tem- 

 perature in the acid previously moderately diluted with water, 

 the salicin dissolves, forming a colourless solution. If a so- 

 lution thus prepared, be poured into cold water, a white pre- 

 cipitate falls down of a resinoid character. This substance 

 is turned red by sulphuric acid ; like the unchanged sahcin, 

 it readily dissolves in alkaline fluids. Submitted to ultimate 

 analysis, this new substance, which from its resinoid characters 

 is termed saliretin^ was found to consist of 



Carbon 72-96 



Hydrogen . . 5*83 

 Oxygen 21-21 



100 



No gas is disengaged during the formation of saliretin ; in- 

 deed the action of the sulphuric acid appears to be purely 

 catalytic, as in the cases of getherification, and the formation 

 of starch-sugar. On examining the acid fluid from which 

 saliretin has been precipitated, it was found to contain grape- 

 sugar ; so that under the influence of the catalytic action of 

 sulphuric acid, salicin is resolved into saliretin and grape- 

 sugar, from the re-arrangement of its elements; affording 

 another example of the resolution of organic products into 

 new arrangements, under the influence of catalysis^ or action 

 of presence. 



Action of Chlorine on Salicin. 



When a current of gaseous chlorine is transmitted through 

 a quantity of salicin diff'used in water, solution ensues, and 

 a yellow fluid is formed ; and if a sufficient quantity of salicin 

 be present, a yellow crystalline mass is deposited. 



These crystals are but slightly soluble in water or alkaline 

 fluids ; they possess a very disagreeable odour and pungent 

 taste ; submitted to analysis, they were found to consist of 

 Atoms. 



Carbon 21 = 126 42-94; 



Hydrogen.. 12 12 4-00 



Chlorine... 2 72 23*65 



Oxygen 11 88 29-41 



Atomic weight . . . 298 100 



so that, by this process, salicin loses two atoms of hydrogen, 

 and gains two atoms of chlorine ; a fact quite conformant with 

 the doctrine of substitution. If the fluid through which the 



