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" bouquet" of the wine ; finally, as they gently stimulate the very 

 sensitive expansion of the nervous bundles that line the roof of the 

 palate, they freshen up the mouth and prepare it to appreciate all 

 the good, bad, or indifferent qualities of the wine. 



If deficient acidity is often the case in warm, countries, it may 

 happen that, on account of accidental loss of foliage or other reason, 

 grapes fail to mature properly, and that the must they yield is poor 

 in sugar and too high in acids. In such a case the remedy which 

 yields the best result is to mix in the fermenting vat some dead- 

 ripe grapes with the acid ones. This method is preferable to that 

 which consists in neutralising part of the acidity of the liquid. 



Saline substances are also found in musts, as potassium salts, 

 under various states of combinations, and chiefly among these is 

 acid tartrate of potash. That salt, commonly known as " argol " 

 or " tartar," adds to the acidity of the must and of new wine. It is 

 less soluble than tartaric acid in water, and its solubility decreases, 

 while the percentage of alcohol goes on increasing. It precipitates 

 in large quantities in the lees after fermentation, and after the first 

 drawing off it deposits slowly, under the form of crystals, on the 

 inside of the casks. 



It often happens that young wines, possessing a raw and 

 unpleasant acid taste, improve considerably on maturing, and lose 

 that excess of acidity which is due to the tartar. 



Although that salt precipitates gradually in a liquid which 

 contains alcohol, that precipitation is further accelerated under the 

 influence of a cool temperature ; hence the practice of maturing 

 wine completely fermented, especially light wines, with a low 

 percentage of alcohol, and with a marked degree of natural acidity, 

 in cool, underground cellars. The French have a characteristic 

 word for depicting that gradual process of precipitation of the 

 tartar and tne lees. They call it depouiller, which means to eject, 

 or excrete the dregs. 



Colouring matters and essential oils, such as produce the 

 "aroma" in wines, are other ingredients of the must. Both are 

 contained in cells which line the inner surface of the skin, and their 

 extraction is made more active and more complete under the 

 influence of heat and the production of alcohol during the course 

 of active fermentation. 



Temperature chiefly influences the solubility of the colouring 

 matter ; alcohol does so to a much lesser extent. This explains 

 why those wines which have been subjected to a fairly high 

 temperature during the process of fermentation are deeper in colour 

 than those fermented at a cooler temperature. If moderate 

 temperature helps in dissolving the colouring matter of grapes, 

 it causes it, if carried on to a higher degree, to undergo an 

 alteration which brings about its precipitation. 



An instance of this is afforded by wines which, during the 

 process of sterilisation by means of heat-process, known by 



