mena, _at the surface_, in the trade-wind region.
Ascending a step higher in the atmosphere, we find, above the
surface-trades, a counter-trade, running, not in the opposite direction,
but at right angles, or nearly so. The counter-trade which issues from the
northern side of the rainy belt, running to the N. W. or W. N. W., and the
counter trade which issues from the southern side, running to the S. W. or
W. S. W., varying, as the trades do in direction in different localities.
These counter-trades are continuations of the surface trades, which,
ascending in their course, have threaded their way through the opposite
trade in the rainy belt, and are continuing on at the same angle, and in
the same direction at which they blew upon the surface, and in obedience
to the same law. This is apparent from several considerations.

1st. They issue at the same angle, and over the top of the surface trades.
In the West Indies and elsewhere, this has been ascertained and proved by
the course of the storms, and the rotation of their surface winds, and
observation.

2d. We can not suppose the N. E. trade to be reflected, and turn back over
itself at a right angle. That would be impossible, even if there were a
wall of solid material there for it to blow against. Air is a peculiar
fluid, and it stratifies with astonishing ease. He who supposes that a
current of air put in motion can be turned aside by another current, or by
the atmosphere at rest, or can be made to mingle, is mistaken. It will
stratify, and force itself onward through the adjacent and opposing
atmosphere, and in a right line. I have observed some remarkable instances
of this character.

3d. The cause which operates to produce the surface trades, still operates
upon the current to carry it over into the other hemisphere; a
counter-trade, as we shall see. It is impossible, therefore, to believe
that the surface-trades as they arrive at the belt of rains and calms,
turn at a right angle, or at any angle, and return: and impossible to
doubt that they pass through each other in this belt, and out at the
opposite side, as upper currents, at the same angle at which they entered.
Of course the N. E. trade of the Atlantic becomes the N. E. counter-trade
of South America, carrying their storms in a S. W. direction, and the S.
E. trade of the Atlantic the S. E. counter-trade of the West Indies,
carrying all their storms in a N. W. direction; and what is true of them
is true of