332 MITCHILL ON THE TERRIBLE SNOW STORM IN 1811. 



southeast, in September, 1304, (ibid. vol. 8. p. 354 — 365.) as examples 

 of my attempts in this branch of meteorology. The present tempest was 

 the more impressive at the time, as having almost immediately followed 

 the terrifying earthquakes of the 17th of the same month, which shook 

 the greater part of North America. With an intention to trace the 

 great currents of our atmosphere, and thereby to furnish additional mate- 

 rials for a correct theory of the winds, I now methodize the facts that 

 have come to my knowledge, concerning a dreadful commotion of the 

 air which happened on the 23d and 24th of December, 1811. 



At the city of Washington, the weather of Monday the 23d was mild ; 

 the sky was clear in the morning. At noon, or a little after, it was 

 overcast, and the wind sprung up at northeast. There was a little rain, 

 which continued until evening, when it ceased. The wind afterward 

 shifted to the northwest, and by ten o'clock at night, blew a furious 

 gale, which continued until morning, and with some abatement, through 

 the whole of the 24th, and the night following. 



The day at JLeesburgh, up the Potomac, as at Washington, was per- 

 fectly clear; but violently windy. The blasts came from the north, 

 and veered occasionally a few points toward the west. 



According to correct observations made at Norfolk, the weather, 

 which had been for some days variable, terminated, on Monday the 

 23d, in a steady rain. On the night of that day, it fell in torrents, until 

 near the break of day, when it was succeeded by a fall of snow and 

 sleet, accompanied by an overwhelming gust of wind from the north 

 and northwest. The air became so intensely cold that the quicksilver 

 fell in the course of the night from fifty to twenty degrees. 



Captain Mills, of the brig Eclipse, experienced the gale on the 23d 

 and 24th. He took it in latitude thirty-six degrees north. It came on 

 very suddenly, and blew with such violence, that he could not lay to. 

 He scudded for sixteen hours, under the goosewings of his foresail, and 



