On Winds. VS 



feveral degrees ueft of it ; and fooner in Finland than in 

 Sweden. (Schwd. Abhandl. 1762, p. 19^5.) And Dr. Frank- 

 lin, in his xxxvith Letter, p. 389, thinks that the north-eall 

 ftorms in North America begin firft, in point of time, in the 

 Ibuih-weft parts; that is to fay, fooner in Georgia than ia 

 Garohna, and fooner in Carolina than in Virginia, &c. He 

 found that a north-eaft ftorm began at Philadelphia at feveii 

 ©'clock, but did not extend to Bolton (about forty miles to 

 the north-eaft) until eleven o'clock. The rcafon of which 

 he well explains, as the current muft begin in the places 

 neareft to that in which the rarefaftion arifes, towards which 

 the current is directed. 



Of Wefterly Winds. 



That eminent and laborious meteorologift C. La Cotte, 

 infers from numerous obfervations of many years, that be- 

 tween latitude 47'^ and 60'' on the weftern fide of our hemi- 

 fphero, the well wind, with fome participation of the north 

 or fouth, is that which obtains ofteneft. (Roz. Jour, xxxix. 

 p. 267.) Leche obtained the fame rclalt at Abo, latitude 60°, 

 from twelve years obfervations; Mufchenbroeck, in Utrecht; 

 Mr. Dalton, in Weftmorland, latitude 54°, (fee his Meteoro- 

 logical fclflavs, p. 48 and 88,) from five years obfervations. 



'["his wind in our continent originates in the Pacific Ocean 

 between the above-mentioned parallels, at Icaft in winter; 

 the air incumbent on that ocean is then much warmer than 

 that of Siberia and Chinefe Tartary that lie weft of it; this 

 therefore preftes upon and flows into the fupra-marine, and 

 is immediatclv fuccceded bv air (lill further weftwards, and 

 thus a current is gradually cftabliftied extending to the At- 

 lantic, which, though in winter, being much warmer than 

 the air of the iflnnds and continent on which it iiows, is 

 forced into the current, both by the rupture of the equili- 

 brium to tiic eaftwards, and bv the prelTure of the ntuch 

 colder air of the continent of North America. 



Of Eajhrly Winds. 



During the winter months there feems to be a frequent 

 flruggle and contcft betwixt the air incumbent over the Afi- 

 atic continent and that incund^ent on the North American 

 lying betwixt the above-mentioned j)arallels and bordering 

 on the Pacific Ocean, which of them ftiall rule over it. 



The niuls of the American air being Id's eonfiderabic, and 

 its cflorts divided between the Pacific and the Atlantic, is 

 generally obliged to yield to its antagonill ; though ionitlinics 

 tht Alialic being wanned, cither by a diilufiou of the fu- 



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