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upon which eleven of tliese tracks were carefully represented. In subse- 

 quent years Mr, Redfield continued his investigations, and in IS46 he 

 published an analysis of three additional hurricanes, making sixteen storms 

 whose tracks are delineated upon his chart of the Atlantic coast. The re- 

 siilts of all these investigations served to confirm substantially the conclu- 

 sions published in 1 833. 



In the Journal of the Franklin Institute for April, 1S36, Mr. Espy 

 co)nmenced the pnblication of a series of essays, in which he announced a 

 new theory of storms; and he has since continued his researches up to 

 the present time. The following generalizations, given in his own words, 

 are the latest at which he has arrived: 



1st. The rain and snow storms, and even the moderate rains and snows, 

 travel from the west towards the east, in the United States, during the 

 months of January, February, and March, which are the only months yet 

 investigated. 



2d. There is a depression of the barometer near the central line of 

 the stonn. 



3d. The central line of minimum pressure is generally of great length 

 from north to south, and moves sideforeniost towards the east. 



4th. This line is sometimes nearly straight, but generally curved, and 

 most Irequenlly with the convex side towards the east. 



5th. The velocity of this hue is such, that it travels from the Mississippi 

 to the Connecticut river in about twenty-four hours; and from the Con- 

 necticut to St. John, Newfoundland, in nearly the same time, or about 

 thirty-six miles an hour. 



6th. When the barometer falls suddenly in the western part of New 

 England, it rises at the same time in the valley of the Mississippi, and also 

 at St. John, Newfoundland. 



7th. In great storms, the wind, for several hundred miles on both sides 

 of the line of minimum pressure, blows towards that line directly or ob- 

 liquely. 



Sth. The force of the wind is in proportion to the suddenness and 

 amount of the barometric depression. 



9th. In all great and sudden depressions of the barometer, there is much 

 rain or snow; and in all sudden great rains or snows, there is a great fluc- 

 tuation of the barometer. 



10th. Many storms are of great and unknown length from north to 

 south, reaching beyond our observers in the gulf of Mevico, on the one 

 hand, and beyond the northern lakes on the other, while their east and west 

 diameter is comparatively small. The storms, therefore, move side- 

 foremost. 



11th. Most storms commence in the '^ far west," beyond the stations of 

 our most western observers; but some commence in the United States. 



12tli. When a storm commences in the United States, the line of mini- 

 mum pressure does not come from the " flu- west," but commences with 

 the storm, and travels with it towards the east. * 



13th. There is generally a lull of wind at the hue of minimum pressure, 

 and sometimes a calm. 



14th. When the wind changes to the west, the barometer begins to rise. 



15tli. There is generally but little wind near the line of maxmunn pres- 

 sure, and on each side of that line the winds are irregular, but tend out- 

 wards from that line. 



