EXAMINATION OF REID'S STORMS. 241 



As the air must necessarily come downwards in the an- 

 nulus where the barometer stands above the mean, "set 

 fair,' 7 for instance, as it did with the Rawlins, we would 

 expect the weather to be without a cloud, and very hot, as 

 it was. Indeed, it would be easy to show, that if the air 

 in the annulus were to come down from a height of four 

 miles, it would be about 45 hotter than it was when it left 

 the surface of the sea in the centre of the storm to go up, 

 for it would bring down with it the caloric of elasticity 

 evolved, as it went up, by the condensing vapor, and the 

 quantity evolved in going up a given height is known if the 

 dew point is given. But the full explanation of this subject 

 is reserved for another occasion. 



The centre of the storm at the moment I have chosen, 

 the noon of the 18th, was between 31 and 32 N. lat., and 

 was at that time moving about N. E., for the centre passed 

 over the Rawlins, and very near to the Yolof, about 150 

 miles to the N. E. of the Rawlins. In this part of its course, 

 it travelled only about 8 miles an hour ; for it passed over 

 the Rawlins at half after 12, in the morning of the 18th, 

 and did not reach the Yolof till 8, P. M., of the same day. 



If this storm was round on the 18th, of which we have 

 no proof to the contrary, there is strong reason to believe 

 it did not long continue round. For on the 21st, it reached 

 from the Westbrook to the West Indian, (Simpson) about 

 700 miles ; so that unless it widened out in like proportion 

 in the other direction, its N. E. and S. W. diameter became 

 greater than that from N. W. to S. E. If this was really 

 the case, as it was in the storm of 1821, and if it moved to- 

 wards the east, then all the phenomena would be easily 

 explained, and the storm of the Wanstead, and the storm 

 of the Clydesdale, Victoria, and Castries, would be one and 

 the same storm. 



This can be ascertained hereafter ; for, in this case, it is 

 probable that Bermuda experienced something of it on the 



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