the various appliances should be large enough so
that not more than one or two volts are lost in the wires. To obtain
the resistance of the wire leading to any appliance, use the following
equation:

Knowing the resistance of the wire, and the total length of the two
wires leading from the plant to the appliance, the size of the wire
may be obtained from a wiring table.

Rubber insulated copper wire covered with a double braid should
preferably be used, and the duplex wire is often more convenient than
the single wire, especially in running from one building to another.
Wiring on the inside of buildings should be done neatly, running the
wires on porcelain insulators, and as directly to the appliance as
possible. The standard rules for interior wiring as to fuses,
soldering joints, etc., should be followed.

Installation

(See also special instructions for the different makes, beginning page
460.)

The room in which the plant is installed should be clean, dry, and
well ventilated. It should be one which is not very cold in winter, as
a cold battery is very sluggish and seems to lack capacity. If
possible, have the plant in a separate room in order to keep out dirt
and dust. If no separate room is available, it is a good plan to build
a small room in a corner of a large room. Keep the room clean and free
of miscellaneous tools and rubbish.

If the entire plant comes complete on one base, all that is necessary
is to bolt the base securely to the floor, which should be as nearly
level as possible. If the battery is to be installed separately, build
a rack. Give the rack several coats of asphaltum paint to make it acid
proof. The location of the battery rack should be such that the rack
will be:

(a) Free from vibration.

(b) At least 3 feet from the exhaust pipe of engine.

(c) Far enough away from the wall to prevent dirt or loose mortar from
dropping on the cells.

Figs. 298 and 299 illustrate two types of battery racks recommended
for use with farm light batteries. The stair-step rack is most
desirable where there is sufficient room for its installation. Where
the space is insufficient to make this installation, use the two-tier
shelf rack. The racks should be made from 1-1/2 or 2 inch boards.

[Fig. 298 "Stair-Step" rack for farm lighting battery]

The cells may be placed on the battery rack with either the face or
the edges of the plates facing out. The latter method requires a
shorter battery r