Indian electricity rules, 1956
[Clause (c) of sub-rule (1)of Rule 21
Specification relating to the deposition of silver
The electrolyte shall consist of a solution of from 15 to 20 parts by weight of silver nitrate in 100 parts of distilled water. The solution must only be used once and only for so long that not more than 30 per cent of the silver in the solution is deposited.
The anode shall be of silver, and the cathode of platinum. The current density at the anode shall not exceed 1/5 ampere per square centimetre and at the cathode 1/50 ampere per square centimetre.
Not less than 100 cubic centimetres of electrolyte shall be used in a voltmeter
Care must be taken that no particles which may become mechanically detached from the anode shall reach the cathode.
Before weighing, any traces of solution adhering to the cathode must be removed and the cathode dried.