238 APPENDIX. 
connection with this process, that the lime will absorb a greater 
quantity of free acid, aud this more rapidly, in a cold than in a warm 
state, in a similar manner as cold water will dissolve more lime than 
warm. After this proceeding, the liquid is strained through cloths, 
and then clarified with nut-galls, or other tannic substances, aided 
by the action of heat, when it is again strained or filtered, and then 
boiled down to a proper consistency for granulation, conformably to 
the method patented by Mr. Wray. 
In a letter from M. Louis Vilmorin, of Paris, bearing date of April 
20, 1857, he says: “ The crystallization of the sugar of the sorgho, it 
seems, should be easily obtained in all cases where the cane can be 
sufficiently ripened ; and, as the proportion of the sugar is an unfailing 
index of ripeness, it follows that we could always be sure of obtaining 
a good crystallization of juices the density of which exceeds 1-075, 
whilst weaker ones could not yield satisfactory results after concen- 
tration. 
“T attribute this peculiarity to the fact that the sugar is preceded in 
the juice by a gummy principle, which seems to be transformed, at a 
later date, for its proportion diminishes in exact correspondence with 
the increase of the saccharine matter. 
“The uncerystallizable sugar, or glucose, undergoes the same 
change ; that is to say, it is more abundant before than after the 
complete maturity ; but its action seems less unfavorable to the pro- 
gress of crystallization. The gummy principle obstructs it in two 
ways ; for, besides being a serious obstacle to the commencement of 
crystallization, it afterward renders it almost a matter of impossibility 
to purge the crystals,if obtained. 
“ However, as I observed, this difficulty only presents itself in the 
employment of unripe canes; for, as soon as the juices attain the 
density of 1-080 and more, they contain but little else than erystalli- 
zable sugar, and their treatment presents no difficulty. 
“The lime employed, even to a slight excess, is not so detrimental, 
it seems to me, in practice, as theory would perhaps indicate. Per- 
haps a slight fermentation, which is inevitable, may disengage enough 
carbonic acid to destroy the uncrystallizable compound formed by its 
union with the sugar. The fact is, that the best crystallizations 
