The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1870-07-06

here. The inquiring reader, who does not
care to take anything for granted, is referred
to the original 'Notice," which is so lucid
and logical as to be easily understood
,,, by any ,,S Glear-hssded S, person pso ia; f1;
peruso it slowly and with steady attention.
We, therefore, simply repes the statement
that the three variations-annual, diurnal,
and azimuthal-observed in the appearance
of shooting stars, instead of contradicting
the astronomical or cosmical theory of that
phenomenon, and furnishing, as was
believed, capital objections to its adop-
tion, are, on the contrary, completely
in harmony with it. According to that,
then, there is reason to think that
shooting stars are due to the earths sue
cessively encountering vast number of
small bodies which circulate in celestial space,
which reach from all quarters with velocities
absolutely equal among themselves, or at
least very nearly equal. Moreover Gt has
been concluded from the characters presented
by the diurnal variation), the velocity in
space of shooting stars must be greater than
that of the earth in her orbit, and but slightly
different from the velocity which would cause
a comet travelling from the depths of space
to make near approach to the EARTH
Another observed fact: At the times when
the phenomenon of shooting stars occurs in
its greatest intensity, namely, about the 18th
and 18th of November, and the 9th and 9th
of August, the shooting stars, instead of
coming indiferently from all the regions of
space, come almost all from determinate di-
rections. One set, those of November,
started from the constellation of the Lion;
the others, those of August, from the con-
stellation Perseus. This circumstance led to
the separation of the shooting stars into
two distinct classes. One class consisted of
the regular streams which the earth periodi-
cally encounters every year, at epochs of the
same date; those are periodical shooting
stars. The others, on the contrary, wander
dering singly in space, in all possible direc-
tions, fall in with the earth indiffer-
emily on all sides; they are called, after
Olbers, sporadic" shooting stars. The
shooting stars of the periodical November
flood have received the special name of
Leonides, from the constellation Lion, whence
they seem to issue; those of the August flood,
in like manner, have received the name of
Perseides.
A further step in the inquiry was this:-M
Schiaparelli, having found the orbit described
by the swarm of the Perseides, afterwards
discovered a remarkable and wholly unex-
pected agreement between it and the orbit of
a large comet observed in 1862, which orbit
is a very efong ated ellipse. This identity of
the two orbits might have been the result of
pure chance, in which case it would have been
of little importance. But second fact of the
C.
cidental coincidence must be given up. The
orbit of the Leonides was found to coincide
with that of comet discovered in the begin
ming Of 1866. The hint being thus unmis-
takably given, by two remarkable instances,
of the coincidence of the orbits of a swarm
of shooting stars and of known comet,
other analogous facts were searched for 1t
was speedily seen that the shooting stars of
December 10 describe in space the same
ellipse as the famous comet of Bella, and,
moreover that the shooting stars of April 10
move in the orbit of the first comet of 1861.
| These results have thrown great light upon
the question of shooting stars. A comet
which follows in space the same route as
swarm of shooting stars must
that swarm. 1t is no other than a local
concentration of the matter of the swarm
a concentration sufficiently intense to render
its mass visible, even at great distances from
the earth. 1t follows that shooting stars are
of the same nature as comets. They consist
of small masses of cometary matter which
circulate in space, unperceived by us in con-
sequence of their diminutive size and only
become visible when they penetrate the
earth's atmosphere. Like comets, or at
least like the legs dense portion of those
heavenly bodies, they are in the state
of gas. All observers are aware that the
fixed stars are visible, without any sensible
diminution of their brightness, through the
tails of comets. Shooting stars present
the same degree of transparency, as was
plainly stated by M. Coulvier-Gravier long
before Schiaparelli's discovery of the iden-
tity of comets and shooting stars. "Eight
times" he wrote in 1869, ''but eight times
only have we seen the nucleus of fixed star
of the first magnitude through shooting
star, also of the first magnitude. If this fact
is confirmed, as believe, it will result that the
matter which gives birth to a shooting me-
teor is transparent"
We are now, therefore, enabled to form a
clear idea of the nature and cause of the phe-
nomenon of the shooting stars, which may be
stated in the following terms-
Masses of nebulous matter, scattered
throughout the stellar spaces, and presenting
a high degree of diffusion, are brought
within the limits of our planetary system
by the paramount influence of the sun. At
the same time, whether by the same action
of the sun or of the large planets near
which they pass, they undergo a progress
sive change of form, in consequence of
which they are drawn out and length
ened into parabolic or elliptic streams or
bands. BY reason of their extreme diff
fuseness, the matter of which they are COM
posed is far from occupying the totality of
the space throughout which their diverse
portions are scattered. Instead of that,
it is divided into multitude of partial
masses, sort of flakes of excessive light
ness, lying more or less apart from one an
other, and having nothing in common but
the simultaneousness of their movements in
directions and with velocities which scarcely
differ from each other.
When the earth, in her travels through
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