mensem, pluvia ventisque carebunt."

Hence, also, in the present day we hear sailors speak of the full and
change, or the quartering of the moon, in connection with a gale at sea;
thus showing, at least, their faith in the influence of the phenomenon.
Yet it is actually the case, at certain times, that in about latitude
40d and 41d, the storms appear about a week apart.

There is some reason, also, to suspect, that there is a difference of
temperature on opposite sides of the sun. As the synodical rotation is
nearly identical with the siderent period of the moon, this would
require about forty-four years to run its course, so as to bring the
phenomena to exact coincidence again. Since these observations were
made, it is understood that Sig. Secchi has determined that the
equatorial regions of the sun are hotter than his polar regions. It may
be owing to this fact, that we have inferred a necessity for a change,
whose period is a multiple of the sun's synodical rotation, but it is
worthy of examination by those who possess the necessary conveniences.

Another period which must influence the character of different years,
depends on the conjunction of the perigee of the lunar orbit with the
node. Taking the mean direct motion of the moon's perigee, and the mean
retrograde motion of the node, we find that it takes six years and one
day nearly from conjunction to conjunction. Now, from the principles
laid down, it follows, that when the perigee of the orbit is due north,
and the ascending node in Aries, that the vortices of the earth will
attain their greatest north latitude; and when these conditions are
reversed, the vortices will reach their highest limit in the lowest
latitude. This will materially affect the temperature of the polar
regions. In the following table, we have calculated the times of the
conjunctions of the apogee and pole of the orbit, taking the mean
motions. It may be convenient to refer to by-and-bye, remembering that
when the conjunction takes place due south, the vortices reach the
highest, but when due north, the vortices in the northern hemisphere
have their lowest upper limit:

CONJUNCTION OF APOGEE AND POLE OF ORBIT.[24]

Year. Month and Day. Longitude.
1804, April 18th, 220d
1810, " 17th, 104
1816, " 16th, 348d
1822, " 15th, 232
1828, " 14th, 116
1834, " 12th, 360
1840, " 1