2th. The opposite period of the year is May 12th--a date,
it is true, on which no great shower of stars is recorded, but sporadic
meteors are very plentiful at that time, and what is more important to
observe is, that the 11th, 12th, and 13th of May, are the three noted
_cold days_ which we have before mentioned. Thus truly indicating that
the earth is then in or near the central plane of the vortex along which
the radial stream is at its maximum of power at any given distance from
the axis.

But the question occurs, does the node of this plane remain stationary,
and is there no variation of the inclination of the axis of the solar
vortex? We have found from observation, that the axis of the terral
vortex is continually oscillating about a mean position by the action of
the moon; and reasoning from this analogy, and the constant tendency of
a material vortex to preserve a dynamical balance, the same tendency
must obtain in the solar vortex under the action of the great planets,
whose orbits do not coincide with the central plane of the vortex. The
ascending node of Jupiter's orbit is in longitude 98d, Saturn's 112d,
Uranus' 72d, Neptune's 131d; so that this plane does not correspond with
the plane of greatest inertia discovered by La Place, and from the
non-coincidence of these planes with the central plane of the vortex,
must produce the same oscillation in the axis of the solar vortex, as
the moon does in the terral vortex, but to what amount, observation can
alone determine. Jupiter and Saturn will of course exert the greatest
influence, and when these two planets are in conjunction, the ascending
node of the central plane of the vortex will vary in longitude perhaps
sufficiently to bring the meteoric maximum at the ascending node into
October on the one hand, and to the close of November on the other, and
at the descending node to April 25th on the one hand, and the close of
May on the other.

The great showers of stars which have been recorded, must be therefore
considered as an accidental exaggeration of a perennial phenomenon,
attaining its maximum when the earth passes through the central plane of
the vortex, whose ascending node in 1833 we will suppose was in
longitude 50d. This theory will therefore account for those great
showers which have occurred about the 24th of April, as well as those
occurring in October and November; for it is far more consonant to all
analogy, to suppose the influx of planetary atom