338 ANALYSIS or WINE. 



and the first, procured from the precipitate of 

 sugar of lead, a copious amount of colouring matter, 

 together with fatty acids. 



We will give an example of analysis of wine con- 

 ducted in this manner, pure Bordeaux being used for 

 the purpose. 



Eed Bordeaux was precipitated with sugar of lead, 

 and the precipitate, a dirty pale blue, placed upon a 

 filter and washed. A violet red liquid passed through 

 the filter. After that which remained upon the filter 

 had been suspended in water, sulphuretted hydrogen 

 was passed through it. The filtered liquid was pale 

 red. After evaporation it deposited a little sul- 

 phide of lead, which was filtered off. After further 

 evaporation it remained of a bright red colour. 



Besides a portion of red colouring matter, tannic 

 acid, albumen, tartaric, racemic, and malic acid might 

 be contained in the liquid, supposing them to exist in 

 the wine. 



Neither gum, sugar, nor extractive matter could be 

 found in the liquid in question, but sulphuric, phos- 

 phoric, and a trace of muriatic acid, though the last 

 would be principally contained in the precipitate of 

 basic acetate of lead. 



A diluted solution of chloride of iron indicated 

 strongly the presence of tannic acid in the red 

 liquid concentrated by evaporation. 



When nitric acid was added to another portion 

 of the liquid in which the tartaric acid had been 



