The Cecil Whig. [volume] (Elkton, Md.) 1841-current, 1861-07-27
Astronomical.

| 1t flourish ! HERCULES 80
Astronomical.
The Mystery of Comets Tails.
There is Eofing in nature more myster.
ious than the growth and motion of tho tails
OF comets. When COMET is first Dissolved
ny telescope 1t generally has no tail. ap-
pearing like faint star seen through haze
as 1t approaches the sun the tail rs deyclo;-
ed, starting ont on the side next the sun. but
being immediately turned back. as if it were
a flame acted on by powerful blast coming
from the sun. The nucleus or head of The
comet is matter, though lighter than the thin
nest fog. but the tail is either no. matter at
ell or it is acted on by forces which do not
manifest themselves on this earth. If the
, IL the train were simply matter, acted on bv
sravitaton, it would follow the head in its
track around the sun, consequently Bending,
as the head sweeps around the part Of its
orbit nearest the sun, into,nearly a senicircu-
lar curve. Instead Of this the train ui,cuus
points from The Sun swinging around as the
stream OF light from lantern in the fog Dies
when the lantern is turned. As the trains
are sometimes of such length that they would
reach from the sun to the earth, and as the
Comet when nearest The sun moves through
many degrees Of its orbit in few hours, the
end oil the train is swept around with veo.
city which forbids the belief Of it's being
matter possessed with the property of inertia.
Inc velocity. too, with which the tail is
Shot forth is irrcconcilable with the idea of
IT'S being subject 20 the law of inertia The
tail OF the great comet Of 1880, Immediately
after It's perIhelion passage. was found by
Newton to have been no less than sixty mil
hons OF miles in length, and to have occupied
only two days in its emission from the comet s
body.
One OF the most singular phenomena of
comets tails is the violent coIn,notion observed
IN them. Flames stream forth from the
nucleus III fan. shaped and various other and
swiftly changing forms. toward the sun at
inst but bending quickly back as il oncoun-
ny furious blast, and then streaming away
millions of miles INTO the sky. This may be
owing to the intense heat to which they are
exposed from their proximity to the SIM -
The great comet Of 1913 approached the sun
within about seventh part of the suns
radius. Sir John llcrschel calculates that at
tins distance the heat of the sun would lie
AZ ,042 times greater than it is at this earth,
aud at least 24i times greater than the heat
IN the focus Of Parker's great lens, which
melted comedian, agate and rock crystal
Usually, rs the comet moves away from the
sun, the train. which it is now pushing partly
before 1t, gradually diminiShcs TIL it disap.
pears altogether. Sometimes, however, the
train Is oblilerated IN the vicinity of the sun,
the comet emerging from the suns light with.
ont any tail whatever. At other Tunes the
tail is the longest just after the perhclion
passage: at Others .here are two or three or
more tails branching out like fan. They
a'r frequently curved like Donali's in 1858.
anu exhibit great variety of singular phcl,-
o"'c''a, which are an incomprchensble mys.
terry to the students of astronomy.
AT about the same time. B,sSel and Prof.
Pierce. each independently of the other,
Offered the suggestion that the trains of comets
may 6e electricity. Perhaps they are simply
light: the sun rays in th-jS passage through
the unknown substance of the nucleus. may
acquire the analogous to polarization
of producing tue vibrations which consti-
tute light.
The heads Of comets are unqncs,onaby
formed Of material substance, as they are
acted on by gravitation. and reflect the sun 5
light but This substance is generally Of ex-
irene tenuity. Stars of the smallest magni.
tudc have been seen through the denSest por.
ton OF the head, and, in the language Of Sir
John Hershel. The most unsubstantial
clouds which float in the highest regions OF
our atmosphere must be looked upon as dense
and massive bodies co,iipared with the tilmy
and al but spiritual texture of comet
In some, however. a very minute stellar point
has been seen. indicating the existence of a