67 



carbonic acid gas is liberated and mixes with the 

 water. The reaction becomes apparent by the effer~ 

 vescence of the liquid, due to the bubbles of car- 

 bonic acid that have been liberated. 



One stage in the manufacture is explained by 

 this fact, which is the principal basis of our system 

 of working. 



As will be afterwards seen, beot juice contains, 

 in addition to sugar and water, different foreign 

 substancts which must be first eliminated, as they 

 tend to decompose and to destroy the sugar and 

 prevent it from crystallizing. Those substances are 

 first azote matters, as albumen, which destroys the 

 sugar by causing fermentation ; coloring matters 

 and different substances held in solution in the 

 liquid. There are also salts of potash and soda of 

 which we will speak later. 



To purify the juice, milk, of lime is used, which, 

 under the influence of heat, decomposes, destroys 

 and precipitates the azote principles and coloring 

 subs tan cep, in an operation which we call defecation 



We have also seen that sugar forms with lime 

 salt called sucrate of lime. 



When the juice is to be purified, it is mixed with 

 a quantity of lime sufficient to combine with the 

 sugar and an excess of lime capable of having 

 complete action overall the foreign azote substances 

 The sugar is thus detached and tiie action of the 

 surplus lime on the foreign substances produces all 

 its effect. But the action of the lime cannot be pro- 



