150 SUGAR. 



in a proper quantity of water; a portion of albumen 

 is added, either blood or white of egg ; the solution 

 is then heated, and the albumen, as it coagulates and 

 separates, entangles and removes all the solid im- 

 purities which the sugar contained. The solution is 

 purified and bleached by filtration through charcoal 

 (162), carefully evaporated, and then allowed to 

 crystallize. The evaporation of the cane juice musj; 

 be carried on as rapidly as possible, but at the same 

 time, exposure to a high temperature is very objec- 

 tionable, because the higher the heat, and the longer 

 the juice is exposed to it, the greater will be the 

 quantity of molasses formed ; a number of ingenious 

 arrangements have consequently been devised to 

 facilitate the evaporation of the solution of sugar at 

 the lowest possible temperature. 



345. Sugar is readily soluble in water, and also 

 dissolves, though less easily in alcohol. When a 

 strong hot syrup is sufi'ered to cool slowly sugar is 

 deposited in large and regular crystals. In the 

 manufacture of sugar-candy, as these crystals are 

 termed, the syrup is left quiet, and strings are sus- 

 pended across it, which assist in the deposition and 

 formation of large and clear crystals. In ordinary 

 sugar-refining, the formation of crystals is not desired, 

 and therefore the solution is continually stirred 

 whilst it is cooling. When sugar is melted, it loses 

 its crystalline character, and becomes barley-sugar : 

 if a very high heat is employed to melt the sugar, it 

 becomes converted into caramel, or burnt sugar; this 



