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it's violence North of the equator, it prevents the 

 atmosphere, that covers the equinoctial lands 

 and seas, from saturating itself with moisture. 

 The hot and moist air of the torrid zone rises 

 aloft, and flows off again toward the poles ; while 

 inferior polar currents, bringing drier and colder 

 strata, are every instant taking the place of the 

 columns of ascending air. By this constant 

 action of two opposite currents, the humidity, 

 far from being accumulated in the equatorial 

 region, is carried toward the cold and temperate 

 regions. During this season of breezes, which is 

 that when the Sun is in the southern signs, the 

 sky in the northern equinoctial zone is constantly 

 serene. The vesicular vapours are not con- 

 densed, because the air, unceasingly renewed, is 

 far from the point of saturation. In proportion 

 as the Sun, entering the northern signs, rises 

 toward the zenith, the breeze of the North-East 

 softens, and by degrees entirely ceases. The 

 difference of temperature between the tropics 

 and the temperate northern zone is then the least 

 possible. It is the summer of the boreal pole ; 

 and, if the mean temperature of the winter, be- 

 tween 42° and 52° of North latitude, be from 

 20° to 26° of the centigrade thermometer less 

 than the equatorial heat, the difference in sum- 

 mer is scarcely from 4° to 6°. The Sun being 

 in the zenith, and the breeze having ceased, the 

 causes that produce humidity , and accumulate 



