206 DOVE ON THE LAW OF STORMS. 
densation of the vapour. This air he supposes to ascend there- 
fore 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 — 
ewt., 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, ‘Theory of Rain, 
Hail and Snow, Waterspouts, Landspouts, Variable Winds and 
Barometric Fluctuations, and examination of Hutton’s, Red- 
field’s, and Olmstedt’s Theories.’ We are indebted to the repeated 
attacks of this author for having given occasion to some excel- 
lent memoirs from Mr. Redfield*. The collection of observations, 
to serve as materials, formed by Mr. Redfield with the greatest 
eare, has further received a highly important augmentation, by 
the magnificent work which the present Governor of the Ber- 
mudas, Lieut.-Colonel Reid, has published on the subjectt. 
Colonel Reid has arrived at precisely the same result as Mr. 
Redfield, and I know by written communications, that both these 
gentlemen have done so quite independently of my earlier re- 
searches. But Redfield and Reid, besides placing on a wider 
basis the rotatory movement which takes place in opposite 
senses in the two hemispheres, have added further some very 
material observations, whose empirical establishment is entirely — 
their own; these I shall now attempt to connect theoretically 
with the rotation movement. 
* Remarks on the prevailing Storms of the Atlantic Coast. (Silliman’s Ame- — 
rican Journal, 20, No. 1.) : 
Hurricane of August 1831. (J'o 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, 12th edit.) ‘ 
On the Gales and Hurricanes of the Western Atlantic. (Sill. Amer. Journ. — 
31, No. 1.) 
Meteorological Sketches, by an Observer. (Sill. Amer. Journ. 33, No. 1.) 
Remarks on Mr. Espy’s Theory of Centripetal Storms, including a Refuta- 
tion 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. 35, No. 5.) 
The Law of Storms. (New York Observer, 18th January, 1840.) 5 
Whirlwinds excited by Fires, with further Notices of the Typhoons of the : 
China Sea. (Sill. Amer. Journ. 36, No. 1.) ; 
+ An attempt to develop the law of storms by means of facts arranged ac- — 
cording to place and time, and hence to point out a cause for the variable — 
winds, with a view to practical use in navigation ; illustrated by charts and 
woodeuts. London, 1838. 
