90 THE CHINESE SUGAR CANE. 
remove the scum and feculencies. Hach defecator ought 
to contain as much as the clarifier into which it dis- 
charges itself. 
CLARIFIERS. 
The first and second clarifiers are two iron pans set 
deep in the brick work, which is lined with light sheet 
copper; so as to add to the size of the pans, a sort of gut- 
ter surrounds these two. The second, which may be a 
little the smallest, should stand about two inches higher 
than the first, so that when it overflows in boiling, its 
contents may be able to flow back into the first kettle, 
but none from the first flow forward into it; the gutter 
which surrounds these two isolates them from the two 
next pans, and has an opening on one side leading toa 
scum, or overflow kettle, set alongside the train and fur- 
nished with a pump, but has no fire under it, being 
merely intended as a recipient for the scum and feculen- 
cies which have not been entirely removed in the 
defecator, and which are swept and skimmed from these 
two pans during rapid ebullition. The overflow is 
pumped back into the clarifiers as soon as it settles, by 
the pump referred to. The peculiar arrangement of the 
the gutter, it is almost impossible to describe without 
diagrams. 
EVAPORATORS. 
Next to the second clarifier comes the first evaporator, 
placed deep in the brick work, and having a sort of curb 
