354 On the Gales of the Atlantic States. 



The heat of the Gulf Stream enables mariners to ascertain 

 by the thermometer when they have entered it : and in 

 winter this heat, by increasing the solvent power of the ad- 

 joining air, loads it with moisture ; which, in a subsequent 

 reduction of temperature, is precipitated in those well 

 ' known fogs, with which the north-eastern portion of our 

 continent, and the neighbouring seas and islands, especially 

 Newfoundland and its banks, are so much infested. An 

 accumulation of warm water in the Gulf of Mexico, ade- 

 quate thus to influence the ocean at the distance of 2,000 

 miles, may be expected in its vicinity to have effects pro- 

 portionally powerful. The air immediately over the Gulf 

 must be heated and surcharged with aqueous particles. 

 Thus it will become comparatively light; first, because it 

 is comparatively warm, and in the next place because aque- 

 ous vapour, being much lighter than the atmospheric an*, 

 causes levity by its admixture. 



Yet the density arising from inferiority of situation in the 

 stratum of air immediaiely over the Gulf, compared with 

 that of the volumes of this fluid lying upon the mountainous 

 country beyond it^ may to a certain extent, more than make 

 up for the influence of the heat and moisture derived from 

 the Gulf: but violent winds must arise, as soon as these 

 causes predominate over atmospheric pressure, sufficiently 

 to render the cold air of the mountains heavier. 



Wi)en instead of the air covering a small portion of the 

 mountainous or table land in Spanish America, that of the 

 whole north-eastern portion of the North American conti- 

 nent, is excited into motion, the effects cannot but be equal- 

 ly powerful, atid much more permanent- The air of the 

 adjoining country first precipitates itself upon the surface of 

 the Gulf, then that from more distant parts.* Thus a cur- 

 rent from the north-eastward is produced below. In the 

 interim the air displaced by this current rises, and^ being 

 confined by the high land of Spanish America, and in part 

 possibly by the trade winds, from passing off in any souther- 

 Jy course, it is of necessity forced to proceed over our part 

 of the continent, forming a south-western current above us. 

 At the same time its capacity for heat being increased by 

 the rarefaction arising from its altitude, much of its mois- 

 ture will be precipitated, and the lower stratum of the soi^tb- 

 western current, mixing whh the upper stratum of the cold 



