COLOUBIffG MATTERS IN WT2TE. 231 



quinine is not pale red, but violet coloured. Quinine 

 first combines with tartaric acid, in which latter ingre- 

 dient the colouring matter is held in solution; tar- 

 trate of quinine, having lost the capability of retaining 

 it, it is then of necessity precipitated. Secondly, 

 the alkaline quinine, although so feebly alkaline, will 

 have some action on the colouring matter of wine, 

 which is so easily affected by alkalies. 



There are, therefore, not one, but three causes for 

 the action of quinine upon red wine. 



Burgundy, when treated in the same manner as 

 Bordeaux, that is, precipitated with sugar of lead, the 

 precipitate decomposed with sulphuretted hydrogen, 

 the sulphide of lead which is separated, washed, and 

 extracted with alcohol and acetic acid, yields a tincture 

 which differs neither in colour nor reaction from that 

 which has been described in speaking of Bordeaux ; 

 that is, supposing the sulphide of lead to be previously 

 freed from the apothema which clings to it ; as it 

 did likewise in Bordeaux. 



The colour of Burgundy does not, therefore, de- 

 pend entirely either upon a peculiar colouring matter, 

 or the admixture of a foreign element, but principally 

 upon smaller contents of free tartaric, or acetic acid. 



We shall see that Burgundy contains exceedingly 

 little acetic acid, less than any other wines which 

 have been analysed. A darker and bluer colour is 

 connected with this smaller amount of free acetic 

 acid. And in fact this is proved in Burgundy. The 



