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‘REPORT OF THE CHEMIST. , 281 - 
through these fans the cane is separated from the lighter leaves much 
as grain is separated from chaff. The leaves are blown away, and 
finally taken from the building by an exhaust fan. This separation 
of the leaves and other refuse is essential to the success of the sugar- 
making, for in them the largest part of the coloring and other dele- 
terious matters are contained. If carried into the diffusion battery 
these matters are extracted (see reports of Chemical Division, U, 8. 
Department of Agriculture), and go into the juice with the sugar. 
_ As already stated, the process of manufacturing sugar is essentially 
-one of separation. The mechanical elimination of these deleterious 
substances at the outset at once obviates the necessity of separating 
- them later and by more difficult methods, and relieves the juice of 
their harmful influences. From the fans the pieces of cane are de- 
_livered by a screw carrier to an elevator, which discharges into 
. THE FINAL CUTTING-MACHINE 
on the third fioor. This machine consists of an 8-inch cast-iron cyl- 
inder with knives like those of a planing-machine. It is really three 
cylinders placed end to end on the same shaft, making the entire 
_ length 18 inches. The knives are inserted in slots and held in place 
with set-screws. The cylinder revolves at the rate of about 1,200 
per minute, carrying the knives past an iron dead knife, which is 
set so close that no cane can pass without being cut into fine chips.* 
From this cutter the chips of cane are taken by an elevator and a 
conveyor to the cells of the diffusion battery, The conveyor passes 
above and at one side of the battery, and is provided with an open- 
ing and a spout opposite each cell of the battery. The openings are 
closed at pleasure by a slide. A movable spout completes the con- 
nection with any cell which it is desired to fill with chips. 
WHAT IS DIFFUSION? 
The condition in which the sugars and other soluble substances 
exist in the cane is that of solution in water. This sweetish liquid 
~ is contained, like the juices of plants generally, in cells. The walls 
of these cells are porous. It has long been known that if a solution 
of sugar in water be placed in a porous or membranous sack and the 
sack placed in water, an action called osmose takes place, whereby 
the water from the outside and the sugar solution from the inside of 
the sack each pass through until the liquids on the two sides of the 
membrane are equally sweet. Other substances soluble in water be- 
have similarly, but sugar and other readily crystallizable substances 
pass through much more readily than uncrystallizable or difficultly 
crystallizable bodies. To apply this property to the extraction of 
sugar the caneis first cut into fine chips, as already described, and 
put into the diffusion cells, where water is applied and the sugar is 
displaced. 
WHAT HAS TAKEN PLACE IN THE DIFFUSION CELLS. 
For the purpose of illustration, let us assume that when a cell has 
- been filled with apie just as much water is passed into the cell as 
there was juice in the chips. The process of osmose or diffusion sets 
in, and in a few minutes there is as much sugar in the liquid outside 
of the cane cells as in the juice in these cane cells; 2. e., the water 
and the juice have divided the sugar, each taking half, Again, as- 
sume that as much liquid can be drawn from one as there was water 
*This machine is the device of Mr. H. A. Hughes. 
