44 
HISTORY OF THE [book v. 
As the fire increases in force, and the liquor 
grows hot, a scum is thrown up, which is formed 
o' the mucilage or gummy matter of the cane, 
with some of the oil, and such impurities as the 
mucilage is capable of entangling. The heat is 
row suffered gradually to increase, until it rises to 
within a few degrees of the heat of boiling water. 
The liquor must by no means be suffered to boil: 
it is known to be sufficiently heated when the scum 
begins to rise into blisters, which break into white 
froth, and appear in general in about forty minutes. 
The damper is then applied, and the fire extin¬ 
guished; after which, the liquor is suffered to re¬ 
main a full hour, if circumstances will admit, un¬ 
disturbed ; during this interval great part of the fe- 
culencies and impurities will attract each other, and 
rise in the scum. The liquor is now carefully drawn 
off, either by a- syphon, which draws up a pure 
defecated stream through the scum, or by means of 
a cock at the bottom. In either case the scum 
sinks down unbroken as the liquor Hows, its tena¬ 
city preventing any admixture. The liquor is re¬ 
ceived into a gutter or channel, which conveys it to 
the evaporating boiler, commonly called the grand 
copper , and, if originally produced from good and 
untainted canes, will now appear almost, if not 
perfectly, transparent.* 
prevents the meliasses from separating from the sugar when it is potted 
or put into the hogshead. 
* Tt* .r.erit of introducing into Jamaica, the clarifiers at present 
in, n e > with syphons and dampers, was claimed by Mr. Samuel 
