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of the storm the vane veered suddenly and with great rapidity 

 through the whole points of the compass, again setting in the 

 south. For the space of three or four hours afterwards it con- 

 tinued very inconstant, changing in all directions, and even- 

 tually settling in the S. W. In the short space of half an 

 hour 1.945 inches of rain fell.' 



" Such were the phenomena at Birmingham as the thunder- 

 cloud passed over it. Its arrival was preceded by oppressive 

 heat and a dead calm, while a fresh breeze blew at Leamington. 

 Its passage was marked by a whirlwind, with constant light- 

 ing, and the fall of nearly two inches of rain in half an hour. 



" Particular circumstances led me to be an attentive observer 

 of the state of the atmosphere from seven to half-past eight on 

 the evening of the 6th of July. I saw the thunder-cloud appear 

 in the south-west, and pass over Birmingham in its course to- 

 wards the north-east ; it was of great extent, and I should think 

 very high ; a rapid current of air in the same direction carried a 

 light scud under the cloud, or at least between me and it, so as 

 to appear under it. The heat was intense thewhole evening, 

 hut previous to and during the storm we had a constant fresh 

 breeze fromthe south-east; thecloudcame from south-west. The 

 lightning was very brilliant and constant, but I heard very 

 little thunder, perhaps owing to the state of the wind. In shape 

 and appearance the cloud might be represented by the map of 

 Africa, from the Bight of Benin southwards, laid on its side, 

 with the eastern coast and the island of Madagascar upper- 

 most. A cloud of the relative size and position of this island 

 kept constantly and steadily in advance of the larger one, and 

 all the lightning which I saw until the cloud passed was from 

 the upper surface, and generally played round the cloud repre- 

 sented by Madagascar, though it sometimes darted out from 

 the latter in every direction. It was forked lightning, but its 

 appearance was not that of bars of light, but such as one 

 would observe were the electric current sent along a zig-zag 

 chain in a darkened room. 



