SUGAR. 361 



tons. That of cane sugar in cane growing countries 

 is incomparably greater. 



910. PRODUCTION. In manufacturing 



How is cane , . 



sugar pro- sugar from the cane, the juice is first pressed 

 out, between heavy iron rollers ; then clar- 

 ified, and finally boiled down until it will crystalize on 

 cooling. The granular crystals form the raw sugar ; 

 the drainings, molasses. Lime is the principal agent in 

 clarification. Its first effect is to neutralize the acid of 

 the juice, which, as before seen, would gradually con- 

 vert the cane sugar into grape sugar, and thus injure 

 its quality. It also precipitates, with other impurities, 

 the gluten, which, as will be hereafter seen, tends to 

 produce more acid. The methods of producing sugar 

 from the beet and maple are essentially the same. The 

 final purification of sugar by bone black has already 

 been described. 



911. MOLASSES. A large portion of 



How may mo- . . 



lasses be con- sugar is ordinarily lost in the form of mo- 

 vertedinto lasses, from which it cannot be made to 



sugar f 



separate by crystallization. This is owing 

 to the presence of impurities not separated by clarifica- 

 tion, which interfere with the process, in a way not per- 

 fectly understood. A method has recently been con- 

 trived of avoiding the loss, and thus largely increasing 

 the product of the beet and cane. Baryta added to the 

 syrup, combines with the sugar, and takes it to the 

 bottom of the vessel, as a solid compound of sugar and 

 baryta, while the impurities remain behind. This pre- 

 cipitate is then removed and diffused in water. Car- 

 bonic acid being added, combines with the baryta, and 



16 



