sitive active material sticks to the separators in
large pieces, Fig. 112, and that remaining in the grids falls out very
easily. The active material has a pinkish color and is badly shrunken.

Rotted, Disintegrated Positives

1. Impurities. This has already been discussed. See page 76.

2. Overheating. The hot electrolyte dissolves the lead of the grids
and that which is dissolved is never converted back to lead. Continued
overheating wears out the grids, and the active material also, and the
plate falls to pieces at the slightest pressure.

3. Age. Positives gradually disintegrate due to the prolonged action
of the electrolyte on the grids, an occasional overheating, occasional
use of impure water, etc.

Positives which are rotted and disintegrated are, of course, hopeless,
and must be junked.

Buckled Positives

As previously described, buckling is caused by unequal expansion. If
the buckling is only slight, the plates may be used as they are. If
the plates are badly buckled, the active material will be found to be
loose, and the plates cannot be straightened. Such positives should be
discarded.

Positives That Have Lost Considerable Active Material

This is the result of continued shedding, the causes of which have
already been given. If the shedding is only slight, and the plate is
good otherwise, it may be used again. If such active material has been
lost, the plates must be discarded.

Positives With Soft Active Material

Continued operation at high temperatures, will soften the peroxide,
and make the plates unfit for further use. Old positives are soft,
clue to the natural deterioration of the paste with age.

Positives With Hard, Shiny Active Material

This condition is found in batteries that have been charged with the
acid below the tops of the plates. The part of the plate above the
acid is continually being heated by the charging current. It becomes
hard and shiny, and has cracks running through it. The peroxide
becomes orange or brick colored, and the grid deteriorates. The part
of the plate below the electrolyte suffers also, as explained more
fully on page 71. Such plates should be discarded if any considerable
portion of the plates is affected. Plates in which 1/2 to 1 inch of
the upper parts are affected may be used again if otherwise in good
condition.

Plates Which Have Been Charged in Wrong Direction

Such plates have been partly reversed, so that there is