A HISTORY OF WORCESTERSHIRE 



a lower figure, although it is probable it made the temperature far less 

 uniform. 



It is only at Birmingham that there are any recorded observations 

 as to solar radiation, sunshine and wind. 



The solar radiation is ascertained by taking the maximum tempera- 

 ture given by a blackened bulb thermometer in vacuo exposed to the 

 direct rays of the sun. The figures given are for the twelve years 

 ending December 31, 1899 — 



The amount of sunshine is measured by a Jordan's sunshine recorder, 

 which is placed on the top of the monument, about 100 feet above the 

 ground. It gives the following figures for the twelve years — 



As to the wind, the pressure is ascertained by Osier's anemometer. 

 The pressure plate presents a surface to the wind of 2 feet superficial. 



The prevailing winds when they blow heaviest are south-west to 

 west, in January, February, March and December. The easterly winds 

 are of longer duration when they come, but do not equal the west or 

 south-west either in velocity or pressure. 



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