CLIMATE £C, NEAR THE MISSISSIPPI. 49 



As this apparent alteration of climate nS5 been remarked only 

 for a few years and cannot be traced up to any \I2P* e natural 

 or artificial change of sufficient magnitude, it would be in v«M] 

 to search for its physical cause. Doctor Williamson and others 

 have endeavoured to show that clearing, draining and cultiva- 

 tion, extended over the face of a continent, must produce the 

 double effect of a relaxation of the rigours of winter, and an 

 abatement of the heats of summer; the former is probably 

 more evident than the latter, but admitting the demonstration 

 to be conclusive, I would enquire whether a partial clearing 

 extending 30 or 40 miles square, may not be expected to pro- 

 duce a contrary effect by admitting with full liberty, the sun- 

 beams upon the discovered surface of the earth in summer, 

 and promoting during winter a free circulation of cold nor- 

 thern air. 



The winds of this country are extremely variable in the 

 winter season, seldom blowing above three days successively 

 from the same point; the north-west wind brings us the seve- 

 rest cold. It may be considered as a general rule during 

 winter, that all winds blowing from the east of the meridian 

 bring rain, and those from the west dry weather; the east and 

 south east winds are most abundantly charged with moisture, 

 as the opposite points are always the driest; the north-east wind 

 during this season is moist chilly and disagreeable, but seldom 

 prevails for any length of time: the north-wind brings (though 

 rarely) sleet or snow. — After 2, 3 or 4 days of damp cloudy 

 or rainy weather, it suddenly clears up with a cold north-west 

 wind, which bio s frequently with great force during the first 

 and sometimes part of the second day of the change, the nights 

 being generally calm ; after a like period of fair weather, of 

 which the two first days are clear and freezing, and the other 

 two l\nc mild and agreeable with a morning's hoar frost, it re- 

 volves again into the same circle of damp and rainy weather. 

 This may be considered as the general revolution of the win- 

 ter season, but with many exceptions. The frequent and ra- 

 pid changes in the state of the weather, during the winter in 

 this climate furnish an excellent opportunity of verifying the 

 vulgar opinion of the moon's pretended infiuer.ee at her con- 

 junctions, oppositions and quadratures; but truth compels me 



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