BY W. ADDISON, ESQ.
107
Maximum, minimum, and mean dew-point, for each month in the year, before stated.
| London. | Malvern. | |||||
| Maximum. | Minimum. | Mean. | Maximum. | Minimum. | Mean. | |
| January | 48.0 | 17.0 | 35.6 | 48.5 | 21.0 | 36.1 |
| February | 45.0 | 22.0 | 36.3 | 49.0 | 30.0 | 38.5 |
| March | 42.0 | 29.0 | 36.5 | 50.0 | 30.0 | 38.6 |
| April | 51.0 | 26.0 | 41.3 | 54.0 | 25.0 | 41.5 |
| May | 56.0 | 26.0 | 41.3 | 54.0 | 25.0 | 41.5 |
| June | 62.0 | 45.0 | 51.5 | 62.0 | 43.0 | 51.1 |
| July | 69.0 | 54.0 | 59.4 | 68.0 | 50.0 | 55.8 |
| August | 67.0 | 49.0 | 59.1 | 54.5 | 47.5 | 55.8 |
| September | 54.0 | 47.0 | 55.8 | 57.0 | 49.5 | 52.8 |
| October | 60.0 | 26.0 | 48.7 | 55.0 | 37.0 | 46.3 |
| November | 58.0 | 34.0 | 43.6 | 58.0 | 28.0 | 40.5 |
| December | 53.0 | 33.0 | 41.3 | 53.0 | 32.0 | 40.0 |
From the foregoing table we obtain the mean dew-point.
| Spring. | Summer. | Autumn. | Winter. | |
| London | 42.0 | 56.6 | 49.3 | 37.7 |
| Malvern | 42.1 | 54.2 | 46.5 | 38.2 |
Mean dew-point, at nine a. m. for the year.[1]
| London | 46.4° |
| Malvern | 45.2° |
When consulting the hygrometer, with a view of ascertaining the greater or less probability of rain, or other atmospheric change, two things are principally necessary to be attended to, the difference between the temperature of the dew-point, and the temperature of the air, and the variations that may
- ↑ The mean dew-point calculated by Mr. Daniell from the daily maxima and minima is 44.5°; the above mean results, it will be remembered, are derived from daily observations at nine a. m.
