at the starting motor be used frequently. This tends to run
the battery down very quickly. Moreover, such a car usually does not
have its engine running long enough to give the generator an
opportunity to keep the battery charged, and to accomplish this, the
charging rate should be increased.

A car which is used mostly at night may need a higher charging rate,
especially if short runs are made, and if the car stands at the curb
with its lights burning. Long night runs will generally call for only
a normal charging rate, since the long charging periods are offset by
the continuous use of the lamps.

A car used on long daylight runs should generally have the charging
rate reduced, because the battery is charged throughout such runs with
no discharge into lamps or starting of motor to offset the continued
charge. If the lamps are kept lighted during such runs, the normal
charge rate will be satisfactory, because the lamp current will
automatically reduce the current sent into the battery.

In the winter time, engines must be cranked for a longer time before
they will start, the battery is less efficient than in warm weather,
and lights are burning for a greater length of time than in summer.
Such conditions require an increase in the charging rate, especially
if the car is used on short runs. Oil long runs in the winter time,
the normal charging rate will generally be satisfactory because the
long charging period will offset the longer cranking period.

In the summer time, engines start more easily than in winter, and
hence require less cranking. The lamps are used for only short periods
and the battery is more efficient than in winter. A lower charging
rate will, therefore, keep the battery charged. Long tours in the
summer time are especially likely to result in overcharged, overheated
batteries, and a reduced charging rate is called for.

How and When to Adjust Charging Rates

A correct charging rate is one which keeps a battery fully charged,
but does not overcharge it, and which does not cause either the
generator or the battery to become overheated. The only way to
determine whether a certain charging rate is correct on any particular
car is to make an arrangement with the car owner to bring in his car
every two weeks. On such occasions hydrometer readings should be taken
and water added, if necessary, to bring the surface of the electrolyte
up to the proper level. The hydrometer readings will show whether