Scientific Intelligence. — Chemistry. 369 



3. On the Grease of' Wines. — White wine is subject to^ an 

 alteration which is designated in Switzerland, and other coun- 

 tries, by the terms greasy and ropy, (tourner au gras, graisser, 

 filer), a change which takes place after the vinous fermentation 

 has apparently ceased, and the wine has been bottled or closely 

 confined in casks. The wines of Champagne, of Switzerland, 

 and most thin and light wines, are very subject to it, especially 

 when the vintage has been wet. The cause of this malady re- 

 sides in a mucilaginous principle which is developed in light 

 wines : it pervades the whole mass, and puts on a reticulated 

 appearance; a similar change is observable in beer, and in 

 syrups made of sugar of an inferior quality. Various methods 

 have been pursued for remedying this defect. Common salt 

 is added to the wine, a practice which was adopted, it is 

 said, by. the Romans, in consequence of an accidental disco- 

 very of an amateur in wines. Having opened an amphora 

 of wine, and being struck with its excellence, he demanded 

 of his slave what he had put in it. The latter, mistaking 

 his master's meaning, fell on his knees and confessed he had 

 drank a little wine and filled up the vessel with sea- water. 

 After two or three months, it is impossible for the most delicate 

 palate to distinguish the taste of salt, and it is admitted that 

 such an addition improves the taste of the wine, but that it pre- 

 vents the grease is a point much more doubtful. Another re- 

 medy is the addition of brandy or alcohol. But the more effi- 

 cacious means of all is a frequent racking off, or decantation. 

 Wine must never be allowed to zvhiten, that is, to admit the 

 rising of a milky substance, which destroys its transparency. 

 When this disease has been contracted, it may often be removed 

 by clarification with fish glue; but this remedy has two incon- 

 veniences, — it does not always succeed, and when it does, it di- 

 minishes the strength of the wine. This deterioration arises either 

 from the glue, or perhaps from the disease itself, which has occa- 

 sioned the operation. Another method of clarifying wines and re- 

 moving the grease, consists in filtering them through shavings of 

 hazel. For small quantities this method is very good. When the 

 sale of wine is not pressing, and care is taken to keep the vases 

 which contain them full, and they are allowed to undergo a slow 

 and insensible fermentation, and are exposed to the change of 

 temperature which the season brings round, this disease spon- 



VOL. XIII. NO. XXVI. — OCTOBEU 1832. A a 



