On the different Qualities of JVines, Jdg 



portion of their oxygen. Wt must however acknowledge, 

 that the supposed absiraction of ihis principle is not essen- 

 tially necessary, since this fermemat'on may be prevented 

 by adding some boiling hot wine to the liquor, as is prac- 

 ticed at Paris, which shows that the ferment undergoes an 

 alteration bv the action of cal'jric. Nevertheless, it is cer- 

 tain, that this substance undergoes a change in its nature 

 by the brimstoning, and is rendered in part insoluble, for 

 the wine becomes turbid by this operation : it also sensibly 

 loses its colour, but this is temporary, for it regains its 

 former colour in a few days. M. Chaptal thinks it advan- 

 tageous to the keeping wines, to preserve them from tho 

 atmospheric air, whose contact is necessary to induce the 

 acid degeneration. 



Fining of IVines. — The two former operations are not 

 always sufficient to impart to the wine that tine limpidity 

 which is so agreeable to the organs of taste and smell, and 

 which so much enhances its value. There still remain in 

 these liquors certain heterogeneous substances which dis- 

 turb the transparency of them, and which do not fall down 

 by siniple rest. In this case, we must have recourse to a 

 third operation called fining, which is generally performed 

 by fish glue, previously softened into a viscid fluid by ma-i 

 ceration in a little of the wine. By this the substances 

 which rendered the wine turbid are carried to the bottom, 

 for we find the wine becomes more limpid, and a sediment 

 is formed, which renders a fresh racking necessary, some 

 time after this substance has-been poured into the wiue, 

 and well mixed with it. The same effect is produced in 

 the iurbid wine by means of ox-blood and the white of 

 eggs. These latter, therefore, may be used to clarify wines, 

 especially the last ; which does not so e.isilv underijo a 

 septic change, and is therefore preFeraii'e in hot climates, 

 and in the summer season. M. Chaptal affirms that gum 

 arabic may be substituted for these gelatmous and albu- 

 minous substances. He even adds, that wine rendered 

 turbid by the lees, may by cleared by a multitude of sub- 

 stances, such as coarse salt, flints calcined and bruised, 

 starch, rice, milk, &c. ; likewise by beech chips, first barked, 

 then boiled in water, and dried in the sun, or in an oven. 

 He attributes the effect of the beech chips upon turbiil wines 

 to a slight fermentation which they induce in the liquorj 

 we may a'so refer the action of starch, rice, and milk, to 

 the same circumstance; whi'st the action of the greatest 

 part of other substances is purely mechanical. But how 



is 



