nference in this paragraph which will bear examination.

1. There is no such regular S. W. wind over the surface trade, as he
supposes. Doubtless, there are, occasionally, secondary S. W. currents
between the counter-trade and the surface one, with partial condensation,
for much of both becomes depolarized by their reciprocal action and
precipitation, and these induced S. W. currents are sometimes so strong as
to usurp the place of the surface-trade, and become very violent in the
latter part of hurricanes; but such is not the usual course of the upper
currents of the West Indies, as the progress of storms there, and
observation, prove.

2. There can not be any _periods_ of extensive and _sudden_ expansion over
Africa. If there is any place on the earth which has a more uniformly
progressive temperature, either way, and is more free from _sudden_
extremes, or which is more arid and destitute of aqueous vapor, and sudden
aqueous expansions, than another, it is Africa. No such occasional sudden
expansions are there possible.

3. Winds do not, and can not, "_encounter_." They stratify upon each
other. They are produced by the action of opposite electricity, and are
_connected together_ in their origin and action. The atmosphere is never
free from the regular and irregular currents, however invisible for the
want of condensation. Aeronauts find them in the most serene days. They
exist without encounter or tendency to rotation, every where, and at all
times; even over the head of the distinguished Professor, whether he
sleeps or is awake. We can all see them when there is condensation, and it
is rarely the case that there is not some degree of it in some of them.

4. That "Great region of expansion" is a chimera. It does not exist. It is
a region of _lower temperature_, and of _condensation_, instead of
_expansion_ of _aqueous vapor_. The trade does not rise in it, or the S.
W. wind overflow from it. See the table cited page 165.

5. The hurricanes do not originate _in the surface trades_, as he
supposes. They originate in the belt of rains, the supposed "region of
expansion," and issue out of it; or in the counter-trade, where volcanic
elevations rise far into or above the surface trade.

6. This hypothesis can not be sustained upon his own principles. The
distance between Africa and the West India Islands, where most of the
hurricanes originate, is from 2,500 to 3,000 miles. These gales are small
when they commence, n