SACCHARUM OFFICINARUM 227 



north of the latitude of 33°. The roots are unable to stand 

 a temperature much lower than i5°F. 



Sugar from Sugar Cane. — The canes, stripped of their 

 leaves, are first shredded by revolving spiked cylinders, and 

 then passed between three different sets of rollers, which 

 crush out the juice. About 75 per cent, of the juice is pressed 

 out by the first set of rollers. Between the first and second 

 set of rollers, the canes are sprayed with the heated juice from 

 the third set. About 10 per cent, of the total amount of 

 juice is removed by the second set of rollers. Before reach- 

 ing the last set of rollers, the crushed material is sprayed with 

 hot water; in this process about 5 per cent, of the total juice 

 is removed. The crushed canes, known as "bagasse," 

 are utiHzed as a fuel to run the mill. 



The juice that flows from the rollers is turbid, due to 

 the impurities which it contains. It is strained, and then 

 milk of Hme is added. The Hmed juice is heated with steam. 

 The impurities unite with the lime, and appear as scum on 

 top or as a sediment at the bottom of the purified juice. 

 The clear juice is run into vacuum evaporators, where it is 

 concentrated to the desired point. The concentrated juice 

 is then pumped into tanks, where crystallization is brought 

 about. 



The grain of the sugar is under the control of the one 

 who has the crystallizing pans in charge. A high temper- 

 ature in the vacuum pans favors the formation of hard- 

 grained sugar; while a low temperature and high vacuum 

 produce a "soft sugar." The mixture of molasses and sugar 

 crystals is termed "massecuite." They are separated by 

 centrifugal action. The sugar crystals are then dried, and 

 packed for shipment. 



By-products of Manufacture. — Cane molasses from the 

 manufacture of white and high-grade yellow sugars is used for 



