o be worked on. Charge the whole battery even though only one cell is
in a very bad condition. This is a method that has been tried out
thoroughly in practice, not in one or two cases, but in thousands.
Batteries in all sorts of conditions have been rebuilt by this method,
and have always given first class service, a service which was
frequently as good, if not better than that given by new batteries.

Examining the Plates

Place an element on a block of wood as shown in Fig. 201. Carefully
pry the plates apart so that you can look down between them and make a
fair preliminary examination. Whenever possible, make your examination
of the plates without separating the groups or removing the old
separators. This should be done because:

(a) Very often the active material is bulged or swollen, and if you
pull out the old separators and put in new ones before charging, the
element spreads out so at the bottom that it cannot be put back into
the jars without first pressing in a plate press. Pressing a complete
element with the separators in place should never be done if it can
possibly be avoided. If it is done the separators should be thrown.
away after you have charged the battery, washed and pressed the
negatives, and washed the positive.

[Fig. 201 Element on block for examination]

(b) If you put in new separators before giving the battery the
preliminary charge, the new separators may pick up any impurities
which may be on the plates, and will probably be cracked by forcing
them between the bulged and sulphated plates. If, however, the old
separators are covered with sulphate, it is best to throw them away
and put in new separators before giving the battery its preliminary
charge, because such separators will greatly hinder the flow of the
charging current. In batteries using rubber sheets in addition to the
wooden separators, remove all the wooden separators and leave the
rubber sheets in place between the plates. Where only wooden
separators are used in a battery, these may be thrown away and
perforated rubber separators used for the preliminary charge. Rubber
separators may be used again. See (a) above about precautions against
pressing a complete element.

[Fig. 202 Separating the groups]

If you are not absolutely certain as to the condition of the plates,
draw out a few separators. If separators stick to the plates, loosen
them by inserting a putty knife blade between them and the plates.
Removing