306 GRAPE CULTURE AND 



was sent to press with over 9 per cent, of solids, as a dead 

 failure, on the seventeenth day ; a vvoful, but in practice but 

 too familiar example of the results of hot fermentations. 



I reserve for the future a detailed discussion of the subject, 

 in connection with other experiments, but the main points 

 illustrated may be briefly thus stated : 



1. While musts of low sugar contents and high acid may 

 be successsully rushed through to dryness at a high tempera- 

 ture and make a sound wine, the same is not true of those 

 having -high sugar and low acid ; the margin of difference be- 

 tween the two cases is a very narrow one, both as to temper- 

 ature, acid, and sugar, and hence a few days of hot "norther" 

 may easily turn the scale. 



2. When the temperature has not been excessively high 

 and not maintained too long, simple aeration by means of a 

 pump or blower may revive it at a lower temperature. Sound 

 pomace, or fresh fermenting must, are additions to be used 

 when available or necessary. 



While these facts and principles are not new to experts, I 

 have thought it worth while to re-establish them by facts and 

 figures, and to offer them as a substitute for the supposed 

 mysteries of "difficult fermentations" that have so vexed 

 our winemakers. The vatting of hot and over ripe grapes 

 and the omission of proper aeration of the mass, while allow- 

 ing the surface to acetify, are responsible for nine-tenths of 

 all unsoundness in California wines. 



E. W. HlLGARD. 



BERKELEY, November, 17, 1887. 



(d) LIQUEUR WINES OR SWEET WINES. CHAMPAGNE. 



This may be said to comprise all the sweet wines, also for- 

 tified wines. These may be made naturally, by leaving the 

 grapes on the vines until over ripe, when, if the must is over 

 28 Balling, it is apt to retain part of the sugar unfermented. 



