Cooley's Cyclopædia of Practical Receipts and Collateral Information in the Arts, Manufactures, Professions, and Trades..., Sixth Edition, Volume II

by Arnold James Cooley; Richard Vine Tuson

2. Hyposulphite bath.

3. Reduction of silver chloride, oxide, or sulphide.

4. Gold waste, α, recovered; β, separated from silver,

5. Paper waste and washings from positive prints.

6. Cyanide solution.

7. Developer.

I. Nitrate Bath,

α, Recovered.

1. Add solution of caustic potash or lime, as long as there is a brown precipitate. Allow to settle, pour off liquid, and collect silver oxide for reduction; vide III, below.

2. For 1 lb. of silver, add 1 oz. sulphuric acid and ¹⁄₂ lb. zinc, and allow to stand two days. Precipitate as chloride, wash eight or ten times by decantation, and dissolve gradually in nitric acid.