ns a considerable altitude where the atmosphere is
comparatively cold, and necessarily loses a portion of its heat there, and
during its northern flow. Probably its central summer range, in the
latitude of Paris, is not far from 55 deg., and with us 60 deg..

The contrast between the trade and the surrounding atmosphere, in winter,
is much more striking, and this has been observed particularly upon the
Brocken of the Alps, and in the polar regions.

"In all seasons the temperature is higher on the Brocken, on a serene,
than on a cloudy day, and, in the month of January, _the serene days were
warmer than at Berlin_." (Kaemtz's Meteorology, by Walker, p. 217.--Note.)

As the portion of the counter-trade, which does not become depolarized--in
diminished volume--progresses toward the polar regions, it settles nearer
the earth, and within the Arctic circle is found but little way above it.
Thus, in December, 1821, Parry, at Winter Island, in latitude 66 deg. 11',
flew a kite, with a thermometer attached, to the height of 379 feet, and
found that the temperature, instead of falling 1-1/4 deg., the usual ratio of
decrease, rose 3/4 of a degree.

The same thing was observed at Spitzbergen, in latitude 77 deg. 30' north, and
at Bosekop, latitude 69 deg. 58', by a scientific commission, and by means of
kites, confined balloons, and the ascent of elevations.

"In winter the temperature goes on increasing with the height, up to
a certain limit, which is variable, according to the different
atmospheric circumstances, the influence of which is not yet very
exactly known. The hour of the day appears to be indifferent, since
there exists no thermometric diurnal variation in the strata of the
surface. The mean of thirty-six experiments, made with kites, or with
captive balloons, at Bosekop, latitude 69 deg. 58' north, has given a
mean rate of increase of 1 deg. 6' for the first hundred meters.[6]
Beyond this limit, and even beyond the first 60 or 80 meters, the
temperature again becomes decreasing, at first very slowly, but
afterward the decrease is accelerated. The observations that have
been made on the flanks, or on the summits, of mountains, during the
same expeditions, entirely confirm these results. The cooling
influence of a soil, that radiates its own heat for several weeks,
without receiving any thing on the part of the sun, in compensation
of it