362 On Storms and Meteorological Observations. 



as the causes known to be active upon the earth's surface can seldom 

 or never produce, at least, upon the scale that he supposes. 



V. It may be objected to the opinions advanced in Mr. Redfield's 

 paper, that the induction upon which they are founded is too narrow, 

 embracing too small a number of particular observations, and these 

 too slightly connected to warrant the conclusions that are drawn from 

 them. The phenomena stated may all be explained upon the sup- 

 position of a whirlwind revolving about a horizontal axis. The prin- 

 cipal movement of a revolving fluid is almost necessarily accompanied 

 by various eddies, counter currents, and motions in an opposite di- 

 rection, and especially must this be the case during the commotion 

 produced by the precipitations and rapid and violent mixtures of air of 

 different temperatures that constitute a furious storm. A good deal 

 of stress is also laid upon the fact, that in certain specified cases, a vio- 

 lent wind from the N. E.. E. S. E. S. or S. W. quarter was suc- 

 ceeded by another from the north ivest. But did this north west 

 wind by sinking down into a calm, after having continued for as long 

 a time as the wind that preceded it, prove itself to be a portion of a 

 retiring whirlwind ? Or did it continue for a longer time — two or three 

 days — with clear weather, and thus shew that it was the first burst of 

 an aerial torrent, by which the current, natural to this part of the 

 earth's surface, was established. When a case shall be adduced 

 where a wind from some other quarter succeeded one from the north 

 west as part of the same storm, the argument drawn from the changes 

 remarked in the course of the wind, will be entitled to more weight 

 and confidence. 



It may be observed farther that in the storms which sweep over the 

 land, and which are of such moderate dimensions, that the direction 

 of the constituent wind can be easily and accurately ascertained ; 

 whirlwinds are of rare occurrence. It is probable, therefore, that 

 the same is true of such tempests as are of larger dimensions, and 

 whose route is either in part or altogether over the ocean. It is a 

 sound rule in philosophy, that when any phenomena, from their vast- 

 ness or for any other cause, cannot be accurately observed, their 

 character is to be inferred from analogous phenomena that are within 

 the reach of observation. 



2.' It is manifest that what has always been regarded as a princi- 

 pal difficulty in accounting for the phenomena of storms — the furnish- 

 ing an explanation of the precipitation of moisture, with the immense 

 evolution of latent heat, and the depression of temperature which 



