374 On (he Anahi/ls of Wine. 



4th, "ExtraSiive matter. The extra^live principle abounds 

 In muft. It appears to be ditiolved in it by tii^' help of the 

 fugar; but when the fermentation changes the nature ot 

 the faccharine principle, the extraftive matter fenfibly de- 

 crea("es. A porrioa brought back then ahnoit to the ftate of 

 fibrine matter i» prtoipitated: ilie depofit is the more len- 

 fible as rhe fermentation flaekens, and as, the alcohol is more 

 abundant. This is what coniiitutes in particular the lees. 

 Theie lees are always mixed with a pretty confidcrable quan - 

 tity of tartar, which it envelops. 



There always exifts ui wine a portion of extractive matter 

 which is in perfect foiution, and from which it may be treed 

 by evaporation. It is more abimdant in new wines than iu 

 oid. The older ihcy grow, they feem to be the more com- 

 pletelv freed from it. 



Thcfe lees, after being dried in the fun or in a ftovc, are 

 well prefled, and then burnt, to extracl that fort ot alkali 

 called in commerce zvood qjhcs. The combultion is eti'eded 

 in a furnace, the fides of v.hich are raifed in proportion as it 

 takes place : the refiduum i> a porous mafs, of a greenilu gray 

 colour, which forms about the thirtieth part of the lees burnt. 



Wines are freed from thcfe lees by drawing them off, in 

 order to preferve them from acid degeneration. 



5th, Aroma. All natural wines have an odour more or Icfs 

 agreeable. There are fome, even, which are indebted for a 

 great part of their reputation to the agreeable odour they 

 exhale. This ^is the cafe with Burgvmdy wine. This per- 

 fume is loft by too tumultuous a fermentation : it becomes 

 flronger by age. It rarely exifts in very* generous wines ; 

 either becaufc it is concealed by the ftrong odour of alcohol, 

 or becaufe the llrong fermentation which has been neceffary 

 to develop the fpirit has extinguifhed or cHflipated it. This 

 aroma does not appear fufceptible of being extraAcd, to be 

 communicated at pjeafure to other fubftanccs. Heat even 

 feenis to deftrov it; for, except (the firft liquid which pafl(?s 

 over by diftillation, and which retain? a liltle of the odour 

 peculiar to wine, the fpirit which comes after has no longer 

 the charafters that effentially belong to it. 



6th, The colouri/inr principle. The colouring principle of 

 wine exifts in the pellicle of the grapes. When the muft is 

 fermented without the ikins, the wine is white. This co- 

 lourinc principle does not difTolve in the vintage but when 

 the alcoht)! is developed in it; and it is only then that the 

 wine becomes cojoured. The colour is ftrongcr according 

 as the fermentation has been more tumultuous, or as it has 

 been left longer in the vat. JSiere preff.n-e of the grapes by 



" treading 



