repairman need not make his truck exactly like that
shown in Figure 117, which is merely shown to give a general idea of
how such a truck should be constructed.

The truck shown in Figure 117 was made from a heavy wooden box. With
this construction lifting batteries is largely eliminated, which is
most desirable, since a battery is not the lightest thing in the
world. The battery is carried in a horizontal position and the truck
is small enough to be wheeled between cars in the shop.

[Fig. 118 Another battery truck]

Another form of battery truck is shown in Figure 118, although this,
is not as good as that shown in Figure 117.

CADMIUM TEST SET AND HOW TO MAKE THE TEST

As the cell voltage falls while the battery is on discharge, the
voltage of the positive plates, and also the voltage of the negative
plates falls. When the battery is charged again the voltages of both
positive and negative plates rise. If a battery gives its rated
ampere-hour capacity on discharge, we do not care particularly how the
voltages of the individual positive and negative groups change. If,
however, the battery fails to give its rated capacity, the fault may
be due to defective positives or defective negatives.

If the voltage of a battery fails to come up when the battery is put
on charge, the trouble may be due to either the positives or
negatives. Positives and negatives may not charge at the same rate,
and one group may become fully charged before the other group. This
may be the case in a cell which has had a new positive group put in
with the old negatives. Cadmium tests made while the battery is on
charge will tell how fully the individual groups are charged.

Since the voltages of the positives and negatives both fall as a
battery is discharged, and rise as the battery is charged, if we
measure the voltages of the positives and negatives separately, we can
tell how far each group is charged or discharged. If the voltage of
each cell of a battery drops to 1.7 before the battery has given its
rated capacity, we can tell which set of plates has become discharged
by measuring the voltages of positives and negatives separately. If
the voltage of the positives show that they are discharged, then the
Positives are not up to capacity. Similarly, negatives are not up to
capacity if their voltage indicates that they are discharged before
the battery has given its rated capacity.

Cadmium readings alone do not give any indicatio