Mr. W. Brown on the Storms of Tropical Latitudes. 207 



We are principally indebted for our knowledge of the phae- 

 nomena of storms to three observers, W. C. Redfield and 

 J. P. Espy of the United States*, and Colonel Reid, whose 

 labours, whether at present successful or not in leading to a 

 full explanation of their action, must ever be regarded with 

 an interest, independent of that which attaches to them merely 

 as important acquisitions to science, because of their being 

 undertaken at the instigation of benevolence, in order if pos- 

 sible to mitigate the sufferings of mariners, by enabling them 

 to escape sooner than they otherwise would from the fury of 

 those terrific scourges of tropical seas. 



J. P. Espy has laboured to show that the direction of the 

 wind during storms is from all parts of their locality towards 

 a central space or line ; for which he accounts by supposing 

 that the air within this space is so expanded by the latent 

 heat emitted by the condensation of vapour, that a rush of 

 air is occasioned from all sides towards it ; a supposition ob- 

 viously contradicted by the indications of the barometer, 

 although it will be seen (fig. 2, page 214) that the directions 

 of the wind observed by him agree with the views here set 

 forth. To W. C. Redfield we owe the discovery of the pro- 

 gressive movement of hurricanes, and the revival of the hy- 

 pothesis that storms are whirlwinds ; an opinion which has 

 been supported by Colonel Reid, and which explains so beau- 

 tifully many of the phaenomena, that it has met with a very 

 favourable reception from many philosophers in this country : 

 nothing however has yet been adduced, as I trust to be able 

 to show, to prove its truth. 



The phaenomena on which this theory is founded are, the 

 various directions of the wind in different portions of the 

 storm, its great velocity compared with the rate of progress 

 of the storm, and the veering of the wind, which generally 

 changes in the northern hemisphere, in the same direction as 

 that of the movement of the hands of a watch on the right of 

 the storm (following the line of its progress), and in the con- 

 trary direction on the left, — all which facts would result 

 from a progressing whirlwind revolving in the contrary di- 

 rection to that of the hands of a watch. In the southern 

 hemisphere the order of the veering of the wind is reversed. 



But it appears to be principally on the two latter points 

 that Redfield rests for the support of his theory ; he says, in 

 his essay on the "Hurricanes of the Atlantic" (American Jour- 

 nal of Science, vol. xxxi. p. 122), "The veering of the wind 

 which so often occurs, when duly considered, is in itself a com- 



* See p. 92 of our last Number.— Edit. 



