NON-NITEOGENOUS ORGANIC CELL-CONSTITUENTS. 119 



test). By means of this test it is claimed that the presence of 0.005 

 grain of inosite ma}- be recognized. In contact with decomposing organic 

 matters inosite may undergo lactic acid or butyric acid fermentation. 



(c) Saccharoses, or Cane-Sugar Group ?i(C 12 H 22 O u ). — This group 

 comprises saccharose, or cane-sugar, lactose or milk-sugar, maltose or 

 malt-sugar, and arabin, found in gum arabic. 



1. Saccharose, or Cane-Sugar (Q a Ti m O a ). — This substance is found 

 widely distributed throughout the vegetable kingdom in the juices of 

 various plants, trees, and fruits. It is derived from changes occurring 

 in starch in the ripening of the fruits. Cane-sugar is said to be the 

 origin of all forms of vegetable sugar, which in the process of vegetation 

 is partly broken up into glucose and hevulose. Cane-sugar ciystallizes 

 in large, colorless rhomboidal prisms, which are soluble in one-third 

 their w r eight of water, the solubility being greatly increased by heat ; 

 thus, at 0° C, 100 grammes of a saturated sugar solution contain 65 

 grammes of sugar ; at 14° C, 66 grammes ; and at 40° C, 75.75 grammes. 

 The solutions of cane-sugar rotate the plane of polarized light to the 

 right (-(-73.80°); with various metallic salts and oxides it forms chemical 

 compounds, which are termed saccharates. When carefully heated to 

 160° C, it melts into a clear, pale, yellowish fluid, which on cooling 

 forms a transparent, amorphous mass — the so-called barley-sugar. If 

 the temperature of 160° is prolonged, cane-sugar is transformed into 

 hevulose and glucose. When subjected to a higher temperature with 

 moisture more profound chemical changes are produced. Carbon dioxide 

 is developed, and a firm, carbonaceous mass containing a trace of 

 brenzcatechin and caramelin may result. In the dry distillation of 

 sugar large quantities of carbon dioxide and small quantities of carbon 

 monoxide and marsh-gas are set free, while the distillate contains acetic 

 acid, as well as substances allied to aldehyde and acetone. Under various 

 circumstances, such as the action of dilute mineral acids, ferments, and 

 prolonged heating of a watery solution in a closed vessel, cane-sugar 

 becomes inverted; that is, divided into a mixture of glucose and 

 laevulose. 



Cane-sugar is not directly fermentable, but when converted into 

 dextrose and laevulose may then undergo fermentations similar to those 

 of grape-sugar. Cane-sugar is easily acted on by oxidizing agents, but 

 less readily than is grape-sugar. It does not reduce alkaline cupric 

 hydrate solutions, nor is it precipitated by acetate of lead, although 

 amnionic lead acetate precipitates it. Strong sulphuric acid chars cane- 

 sugar, but dissolves grape-sugar. Cane-sugar is not directly assimilable 

 by the animal economy. When introduced into the intestinal canal it is 

 first changed into invert sugar before being dissolved. When injected 

 into the veins it is eliminated unchanged by the kidneys. 



