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its 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 condensed, 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, between 42° and 52° of North
latitude, be from 20° to 26° of the centigrade thermometer less than the equatorial heat, the
difference in summer is scarcely from 4° to 6°. The Sun being in the zenith, and the breeze
having ceased, the causes that produce humidity, and accumulate