FERMENTATION. ^1 



Petersburgh ; it was done by means of boiling it a long time 

 in a weak sulphuric acid ; the result has been seized upon, 

 and made the basis of an advantageous mode of rendering 

 fecula fermentable, and extracting from it a spirituous liquor. 

 This process has been brought to such a perfection in France, 

 that the products of the establishments sustain a competition 

 with those of wine and brandy, though the latter may be 

 selling in commerce at a low rate. 



The first step is to mix, in a leaden boiler, concentrated 

 sulphuric acid with water, in the proportion of 3 of acid to 

 100 of water : the temperature of the liquor is then raised 

 to boiling, and the fecula is ijiade, by means of a hopper, 

 to fall gradually into it : the mixture is then stirred forci- 

 bly and the boiling at the same time continued. After six 

 hours the ebullition is stopped ; the acid is then saturated 

 with chalk, and a sulphate of lime is thus formed and quick- 

 ly precipitated. 



When all the deposit has formed, and the liquor become 

 clear, it is carefully racked off and thrown into the vats in 

 which it is to be fermented. These vats are five feet deep 

 and four and a half in diameter ; they are situated in a place 

 where they can be kept constantly at a temperature of from 

 77° to 88|° Fahrenheit. 



The density of the liquor should be from 7° to 8° of the 

 aerometer, (= specific gravity of 1.052 to 1.060.) As soon 

 as the fermentable liquor has acquired the temperature of the 

 distillery, there is mixed with it 44^ lbs. of the beer yeast 

 which is brought from Holland : fermentation takes place in 

 a short time and continues several days ; it sometimes re- 

 laxes in energy, but in a few days the action is renewed with 

 increased activity. 



1 cwt. of potatoes ought to yield from 5^ to 5^ gallons, and 

 this will be the case when the process is well conducted. 

 Starch sells in Paris at from 8 to 9 francs (= about 144 and 

 171 cents) per cwt. 



This brandy has neither a bad taste nor odor, and the 

 manufacturers of liquors prefer it to that made from wine. 



