eat of the sun. It
heats the ocean and the earth--the air is thereby heated and rises, the
cold air rushes in from below, then the ascended current rolls off each
way at the top toward the pole, acquiring a westerly motion from the
rotation of the earth, slipping away from under it, and a different,
_viz._: an easterly motion, after reaching the latitude of 30 deg., from the
_same rotation_; and all the winds and disturbances of the atmosphere are
produced in the same way. They are produced by the action of heated
surfaces upon the adjacent atmosphere."
This is the great theory of meteorologists, by which they attempt to
account for the various atmospherical disturbances, of both tropical and
extra-tropical regions.
The whole theory is a fallacy--it will not stand the test of a careful
examination. The bases of the theory, which are assumed to be facts, are
not so. The agent has not the power claimed for it. A heated surface,
alone, never caused any considerable ascending current, or if it did,
never produced a mile of wind. I repeat it, the theory and all incidental
ones--the thousand explanatory and modifying theories, and
hypotheses--_the whole system_--is without foundation in fact, and will
not bear a critical examination.
Let us see if this language is stronger than the facts will warrant.
The theory assumes that both the land and water, under this central belt,
where the air is supposed to be rising are _materially hotter_ than the
land and ocean are on _either side of it_. Now, how much hotter are the
air and the land under the belt of rains and calms, upon Hindoostan, or
Africa, or South America, where the former is supposed to be acquiring
heat and expansion so rapidly, and to be ascending, than under, and in the
dry belts on either side? None; it is cooler by the thermometer--_much
cooler_.
The central belt of rains in midsummer over Africa, extends up as far as
17 deg. north latitude, and perhaps further. North of this line over the whole
surface of the desert, the Barbary States, a part of the Mediterranean,
and some portion of Italy, the dry season extends, and from the entire
surface the N. E. trade blow into the central belt.[1] Over the desert
they all pass. Now this desert is a sea of sand, under a vertical sun,
intensely heated, blistering the skin with which it comes in contact, and
often acquiring a temperature of 150 deg. to 160 deg. of Fahrenheit. Under the
central belt of rains neither
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