COMPOUND OF SUGAR AND LIME. 



is changed entirely into lactic acid, according to the observations 

 of Fremy. 



A solution of cane sugar is fermented by yeast, but not so 

 readily as grape sugar ; indeed the first action of the yeast is to 

 convert cane sugar into grape sugar, which appears to be the 

 only species of sugar that is directly fermentable (H. Rose) ; 

 diluted sulphuric acid with heat, and tartaric acid likewise effect 

 the latter transformation of cane sugar. The first action of 

 caustic potash in excess upon cane sugar, at the boiling tempe- 

 rature, is similar. A strong syrup mixed with undiluted oil of 

 vitriol becomes hot, swells up, much charcoal is formed, and 

 sulphurous and formic acids disengaged. Sugar is also decom- 

 posed by hydrochloric acid, with the aid of heat, and charcoal 

 liberated. Nitric acid converts it into saccharic, oxalic and 

 carbonic acids, 100 parts of sugar yielding 67 parts of oxalic 

 acid, according to Thenard. Dry chlorine has no action on dry 

 sugar, but syrup absorbs chlorine slowly, and the sugar is con- 

 verted, with disengagement of carbonic acid, into a brown matter, 

 which retains some hydrochloric acid. Sugar dissolves car- 

 bonate of copper and verdigris, forming green solutions, which 

 are not precipitated by alkalies ; the salts, both of copper and 

 peroxide of iron, cease to be precipitated by alkalies when sugar 

 is added to them. Sugar also dissolves lime, barytes and oxide 

 of lead in large quantities, and forms definite compounds with 

 these bases, although in no respect an acid. Sugar is generally 

 viewed as containing two atoms of water of crystallization, which 

 cannot be expelled by heat, without destroying the sugar, but 

 one or both of which are separated in these compounds and 

 replaced by a metallic oxide. 



Compound of sugar and lime; C 12 H 9 O 9 + CaO, HO (Peli- 

 got). When a solution of sugar is digested by a moderate heat 

 with hydrate of lime, a bitter alkaline solution is obtained, in 

 which 100 parts of sugar are united with 56 of lime. The com- 

 pound is less soluble at a high temperature, and the solution, 

 when boiled, becomes a thick gelatinous mass, from which the 

 compound separates as a precipitate, and may be obtained pure 

 by washing with boiling water, in which it is insoluble, or by 

 precipitation with alcohol, which retains any excess of sugar. 

 The solution of this compound absorbs carbonic acid rapidly 

 from the air, and acute rhombohedral crystals of hydrated car- 



