95 



flocks by mineral and vegetable acids. The flocks are a compound 

 of G with acids (according to others pure G.) ; combines with bases; 

 alkalies inci-ease its solubility in water, metallic salts throw the 

 G. down. 



GOflllillt Proximate constituent of carrageen or gcBmon 

 (Chonch'us crispus), and bearer of the mvicilaginous properties of 

 the drug. Contains much nitrogen and sulphur. To prepare it 

 boil the alga with water for a few hours, strarii, precipitate the 

 liquid with alcohol, rinse with alcohol, redissolve in water and 

 evaporate the solution. — Thin, transparent, elastic laminjB similar 

 to isinglass, without smell and taste, swells up in cold water and 

 dissolves when warmed to a mucilage of neutral reaction ; dissolves 

 also in hot hydrochloric and in nitric acid under formation of 

 oxalic acid, in the ordinary mixture of nitric and hydrochloric 

 acid inider formation of suli^huric acid; soluble also in alkalies. 

 Consists of 21-80 C, 4-87 H, 21-36 N, 2-51 S, 49-46 0. 



Grape Sllg'ar, or Dextro-g'lucose, called also from its origin 

 honey sugar, starch sugar, or simply glucose =: C12 H12 O12 + 

 2 HO. Abundantly in sweet fruits, often associated with cane- 

 sugar, always associated with so much Isevo-glucose, that the 

 mixture may be regarded as inverted sugar. (See Fruit Sugar.) 

 It is produced from the juice of gravies by boiling, neutralising 

 the free acid with chalk, evaporating to half the volume, leaving 

 to subside, clarifying with albumen if necessary, and evajjorating 

 to the consistency of a syrup. The Grape-sugar forms into crystals 

 on keeping, and is recrystallised in water. — White, opaque, semi- 

 spherical, or caiiliflower-like mass, consisting of microscopic, sex- 

 angular tabular crystals, tastes less sweet than cane-sugar and at 

 the same time mealy when in the solid state; softens at 60°, 

 deliqiiesces at 90° to 100° under loss of all its water, and solidifies 

 to a colourless amorphous mass; loses at 170° two more equivalents 

 of water, and carbonises afterwards with the odour of burnt sugai-. 

 The fused Grape-sugar deliquesces at the air first under absorption 

 of water, and solidifies again as soon as the quantity of water 

 absorbed is sufficient for the formation of crystals to a crystalline 

 granular mass. The Grape-sugar which has been desiccated with- 

 out fusing (in a current of air of 55° to 60°), and is obtained as a 

 white powder, absorbs no water from the air. Grape-sugar 

 dissolves in 1^ parts cold, in every proportion in boiling water, 

 in 50 parts cold, and in 4 parts boiling alcohol of 0-837, scarcely 

 in ether; but yields with nitric acid, oxalic, no miicic acid; 

 dissolves in cold concentrated sulphuric acid without colouration, 

 but is charred by heat; tui-ns brown on continued boiling with 

 dilute suli^hiu-ic acid; is readily decomposed and turns dark 

 brown when heated with alkalies and alkaline earths, colours the 

 subnitrate of bismuth gi^ey brown when boiled with it under 



