DIFFICULTIES TO BE OVERCOME. 93 
substances of very different chemical properties and rela- 
tions, some of which are yet but imperfectly understood. 
Most of these substances, uncrystallizable themselves, pre- 
vent, by their presence, the sugar from assuming the crys- 
talline form—the only form in which it can be obtained 
pure. In order that we may make sugar, therefore, it is 
necessary to remove first these extraneous substances from 
the saccharine solution. But the means used for this pur- 
pose must be well chosen. They must be adequate; they 
must be of such a kind as to be adapted to ordinary use on 
the large scale; the defecating agents must be harmless to 
health if inadvertently added in excess to the juice, and 
must leave no harmful compounds in any product which is 
afterward to be used as an article of diet; they must be 
sufficiently convenient in form, and low in price, and they 
must not exert an injurious influence upon the constitution 
of the sugar. We find ourselves at once confronted by a 
delicate chemical problem. Here nothing good can be 
accomplished by hap-hazard. We must have a clear view 
of the nature of the material to be acted upon; means 
must be employed commensurate to clearly defined ends; 
the best methods of using such means must be understood, 
and a certain degree of dexterity in their use must be ac- 
quired. And here, as in all other industrial pursuits when 
successfully prosecuted, if a strict adherence to system is 
observed, and if the relations of the successive parts of the 
process to each other are well understood, the different 
operations will be performed with precision and facility, 
and what may have caused much perplexity at first, will 
soon appear perfectly simple. 
Much time would have been gained, and many errors in 
practice would have been avoided, if some important truths 
had been earlier recognized. One of these is that the 
juices of these new canes exhibit properties which are dif- 
