The Republican. [volume] (Oakland, Md.) 1877-current, 1882-07-15
BALLOONS and Comets.

At a meeting of the Balloon Sociey,
M Wilfred de Fonvielle delivered m
interesting lecture on 1.-THE Componnt
parts of Comets The lecturer was m
nouneed as editor of the French scia-
tific periodical H. Electricite, and autbr
of several works on comets, includaq
a description of his midnight obsera-
ton, from balloon, of the last comet
of 1881. In the course OF the evening
the first suggestion of Balloon fSocity
for London was attributed to him. ae
BEGAN by citing Mr.. Spottiswoode, he
President of the Royal Society, for he
statement that the only accurate metbd
of studying the stars was by meansOf
balloons, which opinion the same high
authority backed by strongly recon
mending their use for astronomical pr
poses. The lecturer suggested that he
sudden discovery of great comet else
to the sun during the recent eclipse vas
further reason for experimenting he
telescope. That was not the first n
stance, he added, of the kind, for LOO
years ago Seneca (Nat Quest. VII. O)
stated that Posidonius observed he
transit ola large comet across the scar
disc during an eclipse. Pingre ideti-
fled the eclipse with that observed by In
axagoras in B. G. 462. Reflector
showed that in spite of the growing nun
Der of our observatories, a vast numer
of like objects must escape notice, owho
especially to clouds often of quite mon
siderable density. In these cases Ill,
looms were of the greatest use, as he D q;
self experienced in a free ascent during
last winter. He was astonished a. find
ing that cloud, which had been hover
ing over Paris for more than tire, weeks
and turning day into night, WIS but a
few hundred feet thick. The pethod Of
observation from balloons was applica-
BILE not only to the discovery IF comets
but also to the inferior planets the zodi-
acal light and the Aurora Boealis As
to comets, the most likely accent the
DRY of their nature was that # the Pyth-
agoreans, who imagined cmet to be a
diaphanous body, which hal often been
compared to the glass glole filled with
water, used by horologists b concentrate
the light of lamp on then work, These
ancient astronomers regarded this trans
parent sphere as travelling in its orbit
through the celestial exranse and con-
centrating behind it the solar rays. 1t
had been objected thatno such ball of
gas as M. de Fonvielle deemed almost
every comets nucleus TO be could exist
in space without being absorbed, and
that the comets tail must be part of its
substance, growing as the head dwindled
at perihelion, and conversely. These
objections the lecturer dealt with in de-
tail, arguing that there was no more ne
cessity for the dissipation of the comets
gaseous nucleus than for that of our own
planets atmosphere. :. In discussing the
second objection he spoke of the boards
of comets as well as their tails; these
boards, projecting in direction opposite
to that of the tails, and darling toward
the sun instead of away from it, were
a puzzle, he said, to most of the parti-
sans of the materiality of the tail But
on the optical theory all was consistent.
No dlaphauous body would allow Of the
whole of the light being transmitted di-
rectly through it. There must be short
refraction as well as reflection, so that
comet having tail by reflection must
also have generated beard by retrac-
ton, and these two opposites must q
complimentary to each other. One 81
the principal objects of balloon exploa-
lions would be to investigate this core
lation which generally escaped the 10
tice of land astronomers. because he
boards, projecting in the direction of he
sun, must be more difficult to detect tan
the tails, which receded from it, and
could not be examined except underthe
most favorable circumstances. The most
reasonable explanation was that the
comet lighted up the heavens Just as our
seacoasts were lighted up by an electric
lamp whose rays were projected by a
revolving mirror. -LOnolof, Times