234 MR. E. SCHUNCK ON THE 



equivalents of carbonic acid, and 3 equivalents of water, in 



accordance with the following equation : — 



/ C u H 10 N0 9 1 eq. Indifuscine. 



i r\ • j- • n tr Am ) C 12 H J0 12 1 eq. Indiglucine. 

 leq.OxindicanineC 40 H 23 NO 32 = < u ^ * . ■ 



il 4 U 8 4 eqs. Carbonic acid. 



V H 3 3 3 eqs. Water. 



*-"40 "23 NO32 



The acetic acid which is produced when indifuscine is 

 formed from indicanine does not make its appearance in this 

 case. Indeed the 8 equivalents of oxygen which indicanine 

 absorbs in its conversion into oxindicanine is just sufficient 

 when added to the oxygen already contained in 1 equivalent 

 of acetic acid to convert the carbon and hydrogen of the 

 latter into carbonic acid and water. 



When a solution of indican is evaporated in contact with 

 the air with the assistance of heat, and the residue which 

 remains is treated with strong alcohol there is left undis- 

 solved a brown glutinous substance, which has the properties 

 of oxindicanine but a different composition. The lead com- 

 pound of this substance was prepared by dissolving the latter 

 in water adding acetate of lead, decomposing the precipitate 

 with sulphuretted hydrogen, adding a little acetate of lead to 

 the filtered liquid, filtering again and precipitating completely 

 with sugar of lead. The precipitate which was of a dirty 

 yellow colour was filtered off, and washed first with water 

 and then with alcohol. 



I. 1.3345 grm. dried first in vacuo and then at 100° C. gave 

 0.9875 grm. carbonic acid and 0.2370 water. 



1 .5825 grm. gave 0.4305 grm. chloride of platinum and 

 ammonium. 



0.8960 grm. gave 0.6630 grm. sulphate of lead. 



II. 1.3675 grm. of another preparation gave 1.0485 grm. 

 carbonic acid and 0.2470 water. 



1 .5955 grm. gave 0.4325 grm. chloride of platinum and 

 ammonium. 



