140 CHYMISTRY APPLIED TO AGRICULTURE. 



ARTICLE III., 



Sugar. 



Sugar is a substance' of a sweet and agreeable taste 

 which is extracted from certain vegetables : it is light 

 colored, and when dissolved in water to which a little 

 yeast has been added, is capable of undergoing the vinous 

 fermentation. All those substances that experience the 

 same fermentation by the same means, contain more or 

 less sugar. The same characteristic may be bestowed by 

 art upon many other products of vegetation, causing them 

 to vary, by chymical processes, the proportions of their 

 constituents, till they approach those of sugar; it is in 

 this way that starch and vegetable fibre may be made to 

 undergo the vinous fermentation. All those substances 

 that possess the property of forming the vinous fermentation, 

 may be called by the general name of sugar. There are 

 three kinds of sugar, the characteristics of which are very 

 distinct ; the first and most important is that which crystal- 

 lizes, and to which the generic name of sugar is given ; 

 this is furnished by the sugar cane, the beet, carrot, turnip, 

 chestnut, maple, &.c. 



The sugars procured from these different plants, are, 

 strictly speaking, of the same nature, and do not, when 

 brought by the process of refining to the same degree of 

 purity, differ in any way from each other : their taste, man- 

 ner of crystallization, color, and weight are then precisely 

 the same, and no person, however much in the habit of 

 judging of these products, or of consuming them, can dis- 

 tinguish one from the other. 



The second kind of sugar, is that which is extracted 

 from the must of grapes; this always appears in the form 

 of a white powder, in which no trace of crystallization can 

 be found ; it possesses the properties of the first kind of 

 sugar, and provided a double portion of it be used, an- 

 swers the same purposes. During the time when American 

 sugar was scarce, and consequently excessively dear in 

 France, an enormous quantity of grape sugar was manufac- 

 tured and sold at a low price. 



The third kind of sugar, is that which is contained in 

 nearly all fruits ; this not only refuses to crystallize, but 

 cannot be made to assume solid form. The juices cf 



