52 



except when the air is fully saturated with moisture, the wet-bulb 

 always reads lower than the dry-bulb. This varies from a fraction of a 

 degree, up to twelve or fifteen degrees. If, as is generally done, we 

 estimate the humidity from o up to loo, the former denoting absolutely 

 dry air, and the latter complete saturation; the mean degree of 

 Humidity was 80-5 during the years of observation, and the range of the 

 months from 72 to 92. The driest atmosphere during any one month 

 was in June, 1865, when rain fell on three days only, and the mean 

 temperature of the month was 37" above the average. On May 24th, 

 of the same year, immediately before a thunderstorm, the humidity fell 

 to 45, there being a difference of 13^ degrees between the readings of 

 the dry and wet-bulb thermometers, (7 8 -4° and 64-9° ). The dew point 

 on that occasion was 22*8° lower than the air temperature. 



Table VI. 

 SUMMARY OF RAIN-FALL. 



1862— 1876. 



Rain-fall. 

 From humidity there is a natural transition to rain fall. That for 

 Cockermouth is, as might be anticipated, intermediate between the 

 excessive fall in the mountain districts, and the smaller amount registered 



