now well known, which ought to be familiar to every physical
philosopher. But these speculations of Lieut. Maury will now be
superseded by a new theory of atmospheric movements, an account of
which was presented by its author, Mr. J. Thompson, at the recent
meeting of the British Association for the Advancement of Science. [1]

[Footnote 1: A fuller discussion of this theory the author
reserved for the Royal Society. The _London Athenaeum_ gives a brief
abstract of his paper, in its report of the proceedings of the
Association.]

Mr. Thompson's theory takes account of forces, hitherto unnoticed,
which are generated by the eastward circulation of the atmosphere in
high latitudes. He shows that these forces cause the prevailing
northeastward under-current of our latitudes, while above this, yet
below the highest northeastward current, the air ought still to move
southward according to Halley's theory.

This under-current is not the immediate effect of differences of
temperature, but a secondary effect induced by the friction of the
earth's surface and the continual deflection of the air's eastward
motion from a great circle, (in which the air tends to move,) into
the small circle of the latitude, in which the air actually does move.
The force of this deflection, measured by the centrifugal force of
the air as it circulates around the pole, retards the movement from
the equator, and finally wholly suspends it; so that the upper air
circulates around in the higher latitudes as water may be made to
circulate in a pail; and the air is drawn away from the polar
regions as this circulatory motion is communicated to it, and tends
to accumulate in the middle latitudes, as the circulating water is