and the Method of making Wines . 349 
preserving to them a certain agreeable perfume, give us 
reason to hope for a more happy result of the labours that 
may be undertaken on this subject by persons of ability . 
3. Influence of the Volume of the fermenting Mass on 
Fermentation . 
Though the juice of the grape ferments in a very 
small mass, since I have made it pass through all its pe- 
riods of decomposition in glasses placed on a table ; it 
is nevertheless true, that the phenomena of fermentation 
are powerfully modified by difference of volumes. 
In general, fermentation is the more rapid, speedier, 
more tumultuous, and more complete, as the mass is more 
considerable. I have seen the fermentation of must in 
a cask not terminated till the eleventh day ; while a vat 
filled with the same liquor, and containing twelve times 
the volume of the cask, ended on the fourth day. The 
heat in the cask never exceeded 70 degrees ; in the vat 
it rose to 88. 
It is an incontestable principle, that the activity of fer- 
mentation is proportioned to the mass ; but we must not 
thence conclude that it is always of advantage to carry 
on the process of fermentation in a large mass, or that 
the wine arising from fermentation established in the 
largest vats has superior qualities : there is a term for 
every thing, and there are extremes equally dangerous, 
which must be avoided. To have complete fermentation, 
care must be taken not to obtain it with too great preci- 
pitation. It is impossible to determine the volume most 
favourable to fermentation ; it even appears that it ought 
to be varied according to the nature of the wine and the 
object proposed. If it be the preservation of the aroma, 
it ought to be performed with a smaller mass than when 
it is required to develope all the spirituous part to make 
wines proper for distillation, I have seen the thermome. 
