Accumulator. A term applied to a secondary battery, commonly called a storage-battery.

Accumulator, Electrostatic. (See [Electrostatic Accumulator].)

Accumulator, Storage. A storage-battery.

Acid. A compound of hydrogen capable of uniting with a base to form salts.

Sour, resembling vinegar.

A sharp, biting fluid.

Acidometer. A hydrometer used to determine the gravity of acids. It is employed chiefly in running storage-batteries to determine when the charge is complete.

Adapter. A screw-coupling to engage with different size screws on either end, and used chiefly to connect incandescent lamps to gas-fixtures.

Adherence. The attraction between surfaces of iron due to electro-magnetic action. The term is used in connection with electric brakes—electro-magnetic adherence.

Adjustment. Any change in an apparatus rendering it more efficient and correct in its work.