324 Dove on the Law of Storms. 



had been overthrown, and they found that the tops of all the 

 trees pointed to a centre, the most western trunks lying with 

 their heads towards the east, those to the north with their heads 

 towards the south, the eastern ones towards the west, and the 

 southern ones towards the north. An eye-witness of this storm, 

 Prof. L. C. Beck, maintains, on the contrary, that it was a decided 

 whirlwind, and asserts that no one who beheld it could think 

 otherwise, unless they brought with them previously embraced 

 theoretical views. Mr. Espy's account of the cause of the in- 

 flowing towards a centre is the following : — He considers that 

 when aqueous vapor is condensed into the form of a cloud, it 

 disengages heat, which heat causes the air which contained the 

 vapor to expand six times the loss of volume from the conden- 

 sation of the vapor. This air he supposes to ascend therefore 

 with a velocity of 364 feet in a second, and at the height of 

 hail-clouds to exert on a square foot of surface a pressure of 120 

 cwt., capable of carrying up a cubic block of ice of a foot and a 

 half dimension, or even of lifting an elephant. These conclu- 

 sions, which are termed by Mr. Espy himself " extraordinary 

 and unexpected," are to be found in a memoir consisting of 

 sixteen pages, and bearing the modest title of c Theory of Rain, 

 Hail and Snow, Waterspouts, Landspouts, Variable Winds and 

 Barometric Fluctuations, and examination of Hutton's, Redfield's, 

 and Olmsted's Theories.' We are indebted to the repeated at- 

 tacks of this author for having given occasion to some excellent 







memoirs from Mr. RedfielcL* The collection of observations, 



* Remarks on the prevailing Storms of the Atlantic Coast. (Silliman's Amer- 

 ican Journal, xx, No. 1.) 



Hurricane of August, 1831. (To the editor of the Journal of Commerce.) 



Observations on the Hurricanes and Storms of the West Indies, and of the Coast 

 of the United States. (Blunt's American Coast Pilot, 12lh edit.) 



On the Gales and Hurricanes of the Western Atlantic. (Sill. Amer. Journ. 

 xxxi, No. 1.) 



Meteorological Sketches, by an Observer. (Sill. Amer. Journ. xxxm, No. 1.) 

 Remarks on Mr. Espy's Theory of Centripetal Storms, including a Refutation 



of his Positions relative to the storm of 3rd of September, 1821, with some notices 



of the fallacies which appear in his examinations of other Storms. (Journal of the 



Franklin Institute.) 

 On the Courses of Hurricanes, with Notices of the Typhoons of the China Sea 



and other Storms. (Sill. Amer. Journ. xxxv, No. 5.) 



The Law of Storms. (New York Observer, 18th January, 1840.) 



Whirlwinds excited by Fires, with further Notices of the Typhoons of the China 



Sea. (Sill. Amer. Journ. xxxvi, No. 1.) 



