tmosphere, some being variable and irregular, others
constant, whose action is subject to progressive and fixed laws.

Between the tropics constant causes exercise an action so considerable
that the irregular effects of variable causes are there in some degree
lost; hence result the prevailing winds which in these climates become
established and change at determinate epochs.

Beyond the tropics, and especially toward the middle of the temperate
zones, variable causes predominate. We can, however, still discover
there the effects of the action of constant causes, though much
weakened; we can assign them the principal epochs, and in a great number
of cases make this knowledge turn to our profit. It is in the elevation
and depression (_abaissement_) of the moon above and below the celestial
equator that we should seek for the most constant of these causes.

With his usual facility in such matters, he was not long in advancing a
theory, according to which the atmosphere is regarded as resembling the
sea, having a surface, waves, and storms; it ought likewise to have a
flux and reflux, for the moon ought to exercise the same influence upon
it that it does on the ocean. In the temperate and frigid zones,
therefore, the wind, which is only the tide of the atmosphere, must
depend greatly on the declination of the moon; it ought to blow toward
the pole that is nearest to it, and advancing in that direction only, in
order to reach every place, traversing dry countries or extensive seas,
it ought then to render the sky serene or stormy. If the influence of
the moon on the weather is denied, it is only that it may be referred to
its phases, but its position in the ecliptic is regarded as affording
probabilities much nearer the truth.[58]

In each of these annuals Lamarck took great care to avoid making any
positive predictions. "No one," he says, "could make these predictions
without deceiving himself and abusing the confidence of persons who
might place reliance on them." He only intended to propose simple
probabilities.

After the publication of the first of these annuals, at the request of
Lamarck, who had made it the subject of a memoir read to the Institute
in 1800 (9 ventose, l'an IX.), Chaptal, Minister of the Interior,
thought it well to establish in France a regular correspondence of
meteorological observations made daily at different points remote from
each other, and he conferred the direction of it on Lamarck. This