CHEMICAL COMPOSITION. 187 
IN THE SOLID FORM cane and grape sugar differ in many 
particulars. | 
1. Crystalline form. Cane sugar occurs in the form of 
bold, angular, colorless crystals, having the form of oblique 
six-sided prisms, when a hot saturated solution is allowed 
to cool and evaporate slowly. Crystals rapidly formed are 
generally imperfectly shaped, but present various modifica- 
tions of the regular form. 
Grape sugar, on the contrary, takes the form of minute 
tubercular or wart-like granules (sucre mamelonne of the 
French), which, under the microscope, assume the appear- 
ance of delicate feathery tufts. There is no resemblance 
between the regularly crystallized, brilliant, prismatic cane 
sugar and grape sugar, as will be evident if we compare 
good refined sugar with the white granules on the surface 
of raisins, or the mealy sediment in honey, or in jellies pre- 
pared from acid fruits, such as the American crab-apple or 
currant. 
2. Specific gravity. Cane sugar has a much greater 
specific gravity than grape sugar. The following are av- 
erage results. 
Specific gravity. 
Cane sugar (Rock canay, Pereira)..............cseseceees 1-606 
Grape sugar, crystalline tufts, variable 
WHE GH: OEY NEER wes c<cceentucccsrecs ko essen 1-390 to 1-400 
3. Solubility. One ounce of water at ordinary temper- 
atures, can dissolve three ounces of cane sugar, but only 
two-thirds of an ounce of grape sugar. 
4. Sweetness. The sweetening power (and consequently 
the value) of cane sugar is much greater than that of grape 
sugar, one pound of the former being equal to two and a 
half pounds of the latter. 
5. Fusibility. Pure crystals of cane sugar, heated to a 
temperature of 356° F., melt (impure sugars at a lower 
