I.—Dip the article in a solution of 2 ounces of liver of sulphur and 2 ounces of chlorate soda in 1,000 ounces of water.
II.—Dip the article in a solution of ferrocyanide of potassium very strongly acidulated with hydrochloric acid.
III.—Stir the article about constantly in a solution of liver of sulphur in 50 times its weight of water.
Fusion Point Of Metals.
To Produce Fine Leaves Of Metal.
A thin sheet of polished copper is entered in the bath and connected with the {474} electric conduit. The current precipitates gold on it. In order to loosen it, the gilt copper plate is placed in a solution of ferric chloride, which dissolves the copper and leaves the gold behind. In this manner gold leaf can be hammered out to almost incredible thinness.
Metal Foil.
Tin foil is the most common foil used, being a combination of tin, lead, and copper, sometimes with properties of other metals.
| I Per cent | II Per cent | III Per cent | |
|---|---|---|---|
| Tin | 97.60 | 98.47 | 96.21 |
| Copper | 2.11 | 0.38 | 0.95 |
| Lead | 0.04 | 0.84 | 2.41 |
| Iron | 0.11 | 0.12 | 0.09 |
| Nickel | — | — | 0.30 |
I is a mirror foil; III is a tin foil.