220 MR. E. SCHUNCK ON THE 



0.4420 grm. gave 0.2370 grm. carbonic acid and 0.0925 

 water. 



0.0990 grm. gave 0.0835 grm. chloride of silver. 

 These numbers correspond in 100 parts to 



Carbon 14.62 



Hydrogen 2.32 



Oxygen 14.87 



Oxide of Silver 68.19 



100.00 



This composition approximates, as will be seen, to that of 

 acetate of silver, which consists in 100 parts of 



Carbon 14.37 



Hydrogen 1.79 



Oxygen 14.38 



Oxide of Silver 69.46 



100.00 



The excess in the amount of carbon and hydrogen and the 

 deficiency in that of the oxide of silver show however that 

 it must have contained a small quantity of the silver salt of 

 another acid belonging to the same series as formic and acetic 

 acids, a series having the general formula C n H n 4 . This 

 acid was probably propionic acid, an acid, the formation of 

 which must indeed be assumed, in order to explain how one 

 of the other products of decomposition of indican takes its 

 rise. The quantity of this acid however contained in the 

 silver salt the analysis of which has just been given was very 

 small, since as may be inferred from the composition of the 

 salt, it was to that of the acetic acid in the proportion of 1 

 equivalent of the former to 23 equivalents of the latter. 



Having described all the products to which the decomposi- 

 tion of indican with acids gives rise, it will now be possible 

 to give an account of the manner in which these various 

 products are formed and of the relation in which they stand 

 to one another. 



