VOL. XVIII. (2) CLIMATE & TOPOGRAPHY, CHELTENHAM 143 



The Hours of Bright Sunshine.— 



A daily measurement of bright sunshine has been recorded 

 for 10 years in Cheltenham by a Campbell-Stokes recorder 

 mounted on the top of Pittville Pump Room, and, therefore, 

 well exposed to all horizons. 



The following table gives the approximate bright sunshine 

 in Cheltenham in each of the months in the 10 years 1903- 

 igi2 in hours. 



APPROXIMATE BRIGHT SUNSHINE IN CHELTENHAM, 



TEN YEARS, 1903-12. 



In Hot-rs. 



The amount of bright sunshine experienced naturally bears 

 some relation to the possible amount of sunshine, which varies 

 at different times of the year in accordance with the length 

 of time the sun is above the horizon. From mid- winter to 

 mid-summer and from mid-summer back to mid-winter the 

 dayhght grows longer and then again grows shorter, the arc 

 of the sun's apparent daily course being higher and longer 

 in summer than in winter, and this is the main consideration in 

 determining the number of hours of bright sunshine, so that 

 our expectancy is rightly based when we anticipate more 

 bright sunshine in the summer than in the winter months. 



The increase or diminution of bright sunshine with the 

 change of season is, however, affected by the presence or 

 absence of more or less cloud to obscure the sun's rays, but 



