366 ADULTERATION OF WINE. 



fidence can be felt in the reaction of the wine, even 

 when it is perfectly genuine. 



I must acknowledge that I do not give full confi- 

 dence to any of the reactions recommended for detect- 

 ing foreign colouring matters, and I therefore dismiss 

 them from consideration. They only serve as indica- 

 tions to those who are very expert in analysing wine. 

 I add the following observations, without laying any 

 great weight on them, in order to complete what is 

 already known respecting this matter, and I repeat 

 that the pure colouring matter must be separated, its 

 relation to other substances analysed, and a comparison 

 instituted between it and such foreign colouring mat- 

 ters as are generally used. 



Jacob* has observed, respecting the colouring matter 

 of red wine, that adulteration with the juice of elder- 

 berries cannot be detected by basic acetate of lead, if 

 the juice has been previously fermented. 



Wines of Tonnerre he chiefly examined with alumina 

 and carbonate of ammonia, and obtained the following 

 precipitates : 



Alumina and f 



Cirbonateof S ^ of 



ammonia. 



Natural wine Grey Blue grey. 



The same with logwood Dark violet .... Weak dark blue. 



Brazil wood Carmine, rose . . Wine red. 



Poppy - Slate grey .... Dirty grey. 



Dwarf elder (sambucus ebulus ) . . Bright violet . . . Blue grey, or beau- 

 tiful green. 



Elder (s. nigra) Blue grey .... Dirty green. 



Cornellian cherries (cornus inasc.) Light green.. ..Dirty green 



Litmus Blue green. 



* Journ. de Ch. Med. 1814, Fevr. p. 92, 



