tery is to draw some
up in a hydrometer syringe and add the necessary amount to the cell by
inserting the rubber tube which is at the lower end into the vent hole
and then squeezing the bulb until the required amount has been put
into the cell.

In the summer time it makes no difference when water is added. In the
winter time, if the air temperature is below freezing (32 deg. F), start
the engine before adding water, and keep it running for about one hour
after the battery begins to "gas." A good time to add the water is
just before starting on a trip, as the engine will then usually be run
long enough to charge the battery, and cause the water to mix
thoroughly with the electrolyte. Otherwise, the water, being lighter
than the electrolyte, will remain at the top and freeze. Be sure to
wipe off water from the battery top after filling. If battery has been
wet for sometime, wipe it with a rag dampened with ammonia or baking
soda solution to neutralize the acid.

Never add acid to a battery while the battery is on the car. By "acid"
is meant a mixture of sulphuric acid and water. The concentrated acid,
is of course, never used. The level of the electrolyte falls because
of the evaporation of the water which is mixed with the acid in the
electrolyte. The acid does not evaporate. It is therefore evident that
acid should not be added to a cell to replace the water which has
evaporated. Some men believe that a battery may be charged by adding
acid. This is not true, however, because a battery can be charged only
by passing a current through the battery from an outside source. On
the car the generator charges the battery.

It is true that acid is lost, but this is not due to evaporation, but
to the loss of some of the electrolyte from the cell, the lost
electrolyte, of course, carrying some acid with it. Electrolyte is
lost when a cell gasses; electrolyte may be spilled; a cracked jar
will allow electrolyte to leak out; if too much water is added, the
expansion of the electrolyte when the battery is charging may cause it
to run over and be lost, or the jolting of the car may cause some of
it to be spilled; if a battery is allowed to become badly sulphated,
some of the sulphate is never reduced, or drops to the bottom of the
cell, and the acid lost in the formation of the sulphate is not
regained.

If acid or electrolyte is added instead of water, when no acid is
needed, the electrolyte will become too strong, and sulphate