115 



alone be sufficient to render the wine sweet ; the 

 tartrate of potash would not require to be transformed 

 into carbonate. 



Lastly, it may be well to observe that tartaric acid 

 dissolved in water contributes more than any other 

 organic acid to the production of mould, and thereby 

 induces the formation of cellulose ; this explains the 

 fact, that in test bottles the solution of tartaric 

 acid requires frequent renewal. Cellulose, like sugar, 

 is a substance containing C and HO, and therefore 

 gum and vegetable mucus. It is, therefore, possible 

 when wine has been long in cellar that among other 

 changes tartaric acid may be converted into gum or 

 vegetable mucus. We shall consider, in treating of 

 the odoriferous constituents of wine, the important 

 part played by tartaric acid in the improvement of 

 cellared wine, and next to alcohol this acid may be 

 looked upon as the most important constituent of 

 wine. 



Such wines as contain, in consequence of being 

 cellared, less free tartaric acid (however the effect be 

 produced), will, if red wine, become darker in colour as 

 they sweeten, because a smaller proportion of free 

 tartaric acid allows the blue colouring matter to be- 

 come more evident. 



I can treat better, in another place, of that thicken- 

 ing which is effected in wine by time, and renders it 

 like syrup. I must here mention the unfavourable 

 results of the cellaring of wine, particularly when it is | 



