VOL. XVIII. (2) CLIMATE & TOPOGRAPHY, CHELTENHAM 149 



relative freshness or stuffiness as the case may be which 

 causes respiration to be more or less easy, and which are 

 conditions within everyone's experience. 



The climate of Cheltenham is affected by its position in the 

 country, being West rather than East of the Cotteswold Hills. 

 There is an open sweep from the sea of the Bristol Channel 

 up the Severn Valley, which lies in the direction of the pre- 

 vailing South-West wind. As the town stands upon the foot 

 of the escarpment with widely guarding outliers to North and 

 South, it is protected by a crescent of hills on the Eastern 

 side, and the winds from that side are deflected and broken 

 in force, which renders the climate in Winter and Spring com- 

 paratively less rigorous from the effect of the dry and roughen- 

 ing East wind. It is seldom that the wind blows from the East. 

 Very strong wind from any quarter is comparatively infre- 

 quent in the town. Calms are frequent, and especially about 

 the centre of the town, as in the Promenade, a still air is 

 most usually experienced. 



The very large number of trees and shrubs, which add 

 so greatly to the beauty of Cheltenham, also produce their 

 effect upon the climatic conditions for at least 6 months of the 

 year. Being for the main part trees of deciduous foliage, it 

 can hardly be supposed that their bare boughs can exert any 

 considerable influence during the Winter months. The effect 

 of foliage upon the air is well known. The leaves exercise a 

 sort of respiration, their total effect being to remove some car- 

 bonic acid gas and give forth some oxygen, and in this regard 

 they might be expected to have a freshening effect upon the 

 atmosphere. But this chemical influence is perhaps minor 

 compared to the effect a rich foliage exerts by the water dis- 

 tilled into the air from the leaf surfaces. It is true they 

 intercept some of the rainfall, but when the ground beneath 

 them has been once rendered wet, they greatly interfere with 

 evaporation and retard the drying of the surface. On a clay 

 soil this is very noticeable. Thick foliaged trees further break 

 the force of the wind and help to bring about the calms before 

 referred to as commonly existing in the centre of the town. 

 Beneath their branches the intensity of the daylight is much 

 reduced. 



