4S4 M. H. Bleibtreu on Cumarine. 



Composition of Cumarine. 



Two combustions of cumarine from the Tonka beans gave 

 the following results : — 



I. 0*4870 grm. substance gave 1*3209 carbonic acid and 

 0*1882 water. 



II. 0-6423 grm. substance gave 1*7361 carbonic acid and 

 0*2416 water. 



These numbers correspond in per-centage to 



I. II. 



Carbon . . . 73*97 73*72 



Hydrogen . . 4*29 4*18 



These two analyses correspond exactly with that of the 

 cumarine obtained from the Asperula. In all there is a larger 

 amount of carbon and a smaller quantity of hydrogen than 

 in the analyses of Delalande. 



The expression corresponding to the mean of my experi- 

 ments is C 18 H 6 4 , which contains 1 equivalent of hydrogen 

 less than in Delalande' s formula, as is seen in the following 

 scheme, in which the experimental and theoretical numbers 

 are compared. 



Theory. Bleibtreu. Delalande. 



18 Carbon . 1350 73*97 73*91 72*91 



6 Hydrogen 75 4*11 4*30 4*73 



4 Oxygen . 400 21*97 



1837 100*00 



These experiments leave no doubt as to the identity of the 

 crystalline principle of the Asperula and the stearoptine of 

 the Tonka bean. 



The delightful aroma which characterizes e Maiwein' is en- 

 tirely due to this substance. A liquor artificially prepared 

 w r ith the stearoptine of the Tonka bean met with the warmest 

 approbation from a number of the younger teachers in the 

 University of Bonn. 



Products of Decomposition of Cumarine. 



The new formula for cumarine I endeavoured to control 

 by investigating its products of decomposition. 



Delalande obtained on heating cumarine with concentrated 

 potassa a peculiar acid, HO, C x% H 7 O s , which he described 

 under the name of cumaric acid. According to him, by the 

 continued action of the potassa a further transformation of 

 the latter is effected into that remarkable acid first obtained 

 by Piria as a product of the decomposition of salicine, and to 

 which the attention of chemists has more lately been in the 



