Combustible Subs t a noes. 211 



the management of the fermentation. The 

 more complete the fermentation, the less there 

 is of the oil. 



To this oily matter the ardent spirits owe their 

 different flavours, -for when it is separated they 

 have all the same flavour. It is best distin- 

 guished when the spirit is diluted with water, 

 which renders it milky. The water having a 

 stronger attraction for the spirit than the oil, 

 the oil is in some degree separated, and the fla- 

 vour rendered more sensible. A strong spirit 

 scarcely parts with its oil but in this manner. 



It is generally found that a second process or 

 distillation is necessary, which is called rectifica- 

 tion; thus the spirit is freed from the water and 

 the subtile oils, though it is not always easy to 

 separate them. If, however, the vinous liquor 

 is such as yields a spirit of the purer kind, the 

 second distillation will be sufficient. In this 

 case it is recommended to add a little water. 

 This may seem whimsical, as one end of the 

 distillation is to separate the water ; but the use 

 of it is to get rid of the oil. Water is particu- 

 larly necessary in the rectification of small spirits, 

 when intended for the nicer purposes of phar- 

 macy or compound waters, which ought to have 

 no bad flavour. 



When the quantity of liquor is great, it is 

 easy to obtain some spirit exceeedingly strong, 

 provided the heat at first is slow ; but in small 

 quantities of liquor the spirit can only be ob- 



