analyzed at the sea level and on the tops of
high mountains. Even supposing that to have been the case, the enormous
volume of atmospheric air so charged required to furnish the particles
of a mass of several tons, not to say many masses, is, alone, sufficient
to refute the notion. They can not, either, be projectiles from
terrestrial volcanoes, because coincident volcanic activity has not been
observed, and aerolites descend thousands of miles apart from the
nearest volcano, and their substances are discordant with any known
volcanic product. Laplace suggested their projection from lunar
volcanoes. It has been calculated that a projectile leaving the lunar
surface, where there is no atmospheric resistance, with a velocity of
7771 feet in the first second, would be carried beyond the point where
the forces of the earth and the moon are equal, would be detached,
therefore, from the satellite, and come so far within the sphere of the
earth's attraction as necessarily to fall to it. But the enormous number
of ignited bodies that have been visible, the shooting stars of all
ages, and the periodical meteoric showers that have astonished the
moderns, render this hypothesis untenable, for the moon, ere this, would
have undergone such a waste as must have sensibly diminished her orb,
and almost blotted her from the heavens. Olbers, was the first to prove
the possibility of a projectile reaching us from the moon, but at the
same he deemed the event highly improbable, regarding the satellite as a
very peaceable neighbor, not capable now of strong explosions from the
want of water and an atmosphere. The theory of Chladni will account
generally for all the phenomena, be attended with the fewest
difficulties, and, with some modifications to meet circumstances not
known in his day, it is now widely embraced. He conceived the system to
include an immense number of small bodies, either the scattered
fragments of a larger mass, or original accumulations of matter, which,
circulating round the sun, encounter the earth in its orbit, and are
drawn toward it by attraction, become ignited upon entering the
atmosphere, in consequence of their velocity, and constitute the
shooting stars, aerolites, and meteoric appearances that are observed.
Sir Humphry Davy, in a paper which contains his researches on flame,
strongly expresses an opinion that the meteorites are solid bodies
moving in space, and that the heat produced by the compression of the