HOW TO MAKE A PAPER BAROMETER
Question.—J. K. writes: Can you tell me how a Barometer can be made with paper that tells what the weather is going to be?
Answer.—Paper barometers are made by impregnating white blotting paper in the following liquid, and then hanging up to dry:
| Cobalt Chloride | 1 oz. |
| Sodium Chloride | ½ oz. |
| Acacia | ¼ oz. |
| Calcium Chloride | 75 gr. |
| Water | 3 fl. oz. |
The amount of moisture in the atmosphere is indicated by the following colors:
| Rose Red | Rain |
| Pale Red | Very Moist |
| Bluish Red | Moist |
| Lavender Blue | Nearly Dry |
| Blue | Very Dry |