as used at the Parkinson factory, consists of twelve iron tanks. (See
diagram.) They are arranged in a line, as shown in diagram, Fig. 1. Each
has a capacity of seventy-five cubic feet, and by a little packing holds
a ton of cane chips. The cells are supported by brackets near the
middle, which rest on iron joists. Each cell is provided with a heater,
through which the liquid is passed in the operation of the battery. The
cells are so connected by pipes and valves that the liquid can be passed
into the cells, and from cell to cell, at the pleasure of the operator.
The bottom of each cell consists of a door, which closes on an annular
rubber hose placed in a groove, and filled with water, under a pressure
greater than that ever given to the liquids in the cell. This makes a
water tight joint whenever the trap door bottom is drawn up firmly
against it. The upper part is of cast iron and is jug shaped, and is
covered with a lid which is held with a screw on rubber packing. In the
jug neck and near the bottom the sides are double, the inner plates
being perforated with small holes to let water in and out. The bottoms
are double, the inner plates being perforated like the neighboring
sides, and for the same purpose. The cells, of whose appearance a fair
idea may be had from diagram, Fig. 2, are connected with a water pipe, a
juice pipe, a compressed air pipe, and the heaters, by suitable valves.
The heaters are connected with a steam pipe. This, and the compressed
air pipe, are not shown in the diagram. The water pipe is fed from an
elevated tank, which gives a pressure of twelve pounds per square inch
The valve connections enable the operator to pass water into the cells
at either the top or the bottom; to pass the liquid from any cell to the
next, or to the juice pipe through the heater; to separate any cell from
any or all others, and to turn in compressed air.

Now let the reader refer to Fig. 2.