HYGROMETERS AND HYGROSCOPES:
Paper Hygrometers.
| Cobalt chloride | 1 ounce |
| Sodium chloride | 1/2 ounce |
| Calcium chloride | 75 grains |
| Acacia | 1/4 ounce |
| Water | 3 ounces |
The amount of moisture in the atmosphere is roughly indicated by the changing color of the papers, as follows:
| Rose red | rain |
| Pale red | very moist |
| Bluish red | moist |
| Lavender blue | nearly dry |
| Blue | very dry |
Colored Hygroscopes.
| I.— | Cobalt chloride | 1 part |
|---|---|---|
| Gelatin | 10 parts | |
| Water | 100 parts |
The normal coloring is pink; this color changes into violet in medium humid weather and into blue in very dry weather.
| II.— | Cupric chloride | 1 part |
|---|---|---|
| Gelatin | 10 parts | |
| Water | 100 parts |
The color is yellow in dry weather.
| III.— | Cobalt chloride | 1 part |
|---|---|---|
| Gelatin | 20 parts | |
| Nickel oxide | 75 parts | |
| Cupric chloride | 25 parts | |
| Water | 200 parts |
The color is green in dry weather.
HYOSCYAMUS, ANTIDOTE TO: See Atropine.