ii6 POPULAR SCIENCE MONTHLY, 



Other articles confirming the position first taken followed, 

 among them one on the hurricanes and storms of the West Indies 

 and the coast of the United States, and the uniformity of their 

 general character, in which the storms of the China Sea were 

 shown to be similar to those of the West Indies, and the gyrations 

 in the southern hemisphere to be opposite to those in the north- 

 ern ; one presenting a general view of the atmosphere and its cur- 

 rents, and a classification of storm winds, predicating the identity 

 of whirlwinds and water spouts, and discussing the great aerial 

 currents ; and articles on tidal movements, climate as connected 

 with atmospheric and oceanic currents, the Gulf Stream, and polar 

 currents. 



The main features of Mr. Redfield's theory of storms, as stated 

 by Prof. Olmsted, are : 



" That all violent gales or hurricanes are great whirlwinds, in 

 which the wind blows in circuits around an axis either vertical or 

 inclined ; that the winds do not move in horizontal circles, but 

 rather in spirals toward the axis a descending spiral movement 

 externally and ascending internally. 



"That the direction of revolution is always uniform, being 

 from right to left or against the sun on the north side of the 

 equator, and from left to right or with the sun on the south side. 



"That the velocity of rotation increases from the margin 

 toward the center of the storm. 



" That the whole body of air subjected to this spiral rotation 

 is, at the same time, moving forward in a path at a variable rate, 

 but always with a velocity much less than the velocity of rota- 

 tion, being at the minimum, hitherto observed, as low as four 

 miles, and at the maximum forty-three miles, but more com- 

 monly about thirty miles an hour, while the motion of rotation 

 may be not less than from one hundred to three hundred miles 

 per hour. 



" That in storms of a particular region, as the gales of the At- 

 lantic or the typhoons of the China Sea, great uniformity exists 

 in respect to the path pursued ; those of the Atlantic, for example, 

 usually issuing from the equatorial regions eastward of the West 

 India Islands, pursuing at first a course toward the northwest as 

 far as the latitude of 30, and then gradually wheeling to the 

 northeast and following a path nearly parallel to the American 

 coast, to the east of Newfoundland, until they are lost in mid- 

 ocean, the entire path when delineated resembling a parabolic 

 curve whose apex is near the latitude of 30. 



" That their dimensions are sometimes very great, being not 

 less than one thousand miles in diameter, while their path across 

 the ocean can sometimes be traced for three thousand miles. 



" That the barometer, at any given place, falls with increasing 



