Now let the reader refer to Fig. 2.

[Illustration:  Fig. 2—­DIFFUSION PROCESS—­MANUFACTURE OF SORGHUM SUGAR.]

The cutters are started, and cell 1 is filled with chips.  This done, the chips from the cutters are turned into cell 2; cell 1 is closed, and cut off from the others, and water is turned into it by opening valve, c, of cell 1 (see Fig. 2) until it is filled with water among the chips.  When 2 is filled with chips, its valve, a, is raised to allow the liquid to pass down into the juice pipe.  Valve a of 3 is also raised.  Now the juice pipe fills, and when it is full the liquid flows through valve, a, of 3, and into the heater between 2 and 3, and into the bottom of 2, until 2 is full of water among the chips. (This may be understood by following the course of the arrows shown in the diagrams of 9 and 10).  Valve a of 2 is now screwed down; c is down and b is opened.  It will be readily seen by attention to the diagram that this changes the course of the flow so that it will no longer enter at the bottom, but at the top of 2, as shown by the arrows at cell 2.

It is to be observed that the water is continually pressing in at the top of 1, and driving the liquid forward whenever a valve is opened to admit it to another cell, heater, or pipe.  When cell 3 is full of chips, its valves are manipulated just as were those of 2.  So as each succeeding cell is filled, the manipulation of valves is repeated until cell 6 is filled with liquid.  After passing through six cells of fresh chips, this liquid is very sweet, and is drawn off into the measuring tank shown at p in diagram, Fig. 1, and is thence conveyed for subsequent treatment in the factory.  To draw this juice from 6, valve a of 7 is raised to connect the heater between 6 and 7 with the juice pipe.  A gate valve in the juice pipe is opened into the measuring tank, and the pressure of water into the top of 1 drives the liquid forward through the bottom of 1, through the heater, into the top of 2, out from the bottom of 2, through the heater into the top of 3, out from the bottom of 3, through the heater into the top of 4, out from the bottom of 4, through the heater, into the top of 5, out from the bottom of 5, through the heater, into the top of 6, and now out from the bottom of 6, through the heater, into the juice pipe, and from the juice pipe into the measuring tank.  It will be understood that the liquid which is drawn from 6 is chiefly that which was passed into 1 when it was filled with chips.  There is doubtless a little mixing as the pressure drives the liquid forward.  But the lighter liquid is always pressed in at the top of the cells, so that the mixing is the least possible.  The amount of liquid, now called juice, which is drawn from 6 is 1,110 liters, or 291 gallons.  When this quantity has been drawn into the measuring tank, the gate valve is closed, and the valves connecting with 7 are manipulated as were those of 6, a measure of juice being drawn in