A CHAPTER IN METEOROLOGICAL DISCOVERY. 791 



pared his facts, before lie published his theory of storms. He 

 noted the occurrence of several great gales, and set about collect- 

 ing all the facts possible in reference to them, carrying on a wide 

 correspondence, and examining a multitude of witnesses. He 

 sought out the marine reports as to all vessels coming into port 

 soon after the storm, examined their log-books and talked with 

 their captains. In the case of the great Cuban hurricane of 1844, 

 he collated one hundred and sixty-four different accounts. He 

 noted the latitude and longitude of the vessels at sea, or the ob- 

 servers on the coast, when they took the gale, the direction and 

 force of the wind as they experienced it, the direction in which 

 it veered, the states of the barometer, and all cognate facts. 

 Then he charted the whole and studied its meaning. 



It was in 1831, ten years from the time in which he first ob- 

 served the effects of the September gale and drew his inferences 

 from them, that he published an article, " On the Prevailing 

 Storms of the Atlantic Coast." In it he gave an account of the 

 gale of 1821, which he describes as " exhibited in the form of a 

 great whirlwind." He had now made several important conclu- 

 sions in reference to this class of storms : 1. He held that they 

 often originate in the tropical latitudes, frequently to the north 

 and east of the West India Islands. 2. That they often cover at 

 the same moment of time an area of from one hundred to five 

 hundred miles in diameter, and that they are most violent nearest 

 the center of this area, and least energetic about the exterior 

 lines. 3. That while in the tropics these storms move from east 

 to west till they reach the parallel of 30 north, when they sud- 

 denly recurve to the north and east, and move rapidly along lines 

 generally parallel with the Atlantic coast of the United States. 



4. That the direction of the winds along the greater portion of its 

 storm-tracks is not the same as the direction of the storm itself '. 



5. That when in these northerly latitudes these storms, while 

 moving in a northeast course, begin with a wind from east to 

 south, and terminate with a wind from west to north. 6. That 

 on the outer portion of the track, north of the parallel of 30 or 

 within that portion lying farthest from the American coast, these 

 storms exhibit at the commencement a southerly wind which, as 

 the storm comes over, veers gradually to the westward, a quarter 

 where it is found to terminate. 7. In the same latitudes, but 

 along the central portion of the track, the first force of the wind 

 is from the southeast, but after blowing for a certain period it 

 changes suddenly to a point nearly or directly opposite. 8. On 

 that portion of the track nearest the American coast or farthest 

 inland, if the storm reaches the continent, the wind commences 

 from an east or northeast point and veers more or less gradually 

 by north to northwest. 



