Alexandria gazette. [volume] (Alexandria, D.C.) 1834-1974, 1858-10-05

NJ. Mitchell, OF tue CIuclnn I'll Observatory,
communicates to the Daily Gazetei very IN
terestiug paper regarding the Comet which
now makes 30 fine display in our Western
heavens at night. IL was discovered by Pro-
lessor Donati, of Florence, Italy, nearly four
months ago, and for a lorger portion OF the
time since 1t Wa detected, nas been steadily
approaching the earth, and in direction g.
nearl eolncident with the visual ray, that tut
for the computations OF Astronomers. might
we'll excite autcpations OF some fearful coins
ion With our planet. Indeed. throughout the
present u ath it e. ems to baye been plunglDg
downward so exactly toward the earth, that
it scarcely changed its apparent place among
the fixed stars by quantity larger than two
or three times the diameter of the moon.
II will reach its nearest approach to the
sun in a few DAYS. Its briliancy will in-
crease rapidly up 10 the first week IN October,
when it will put on it's mos. splendid appear
ance, and will then rival in grandeur the ia
nous Comet of HALEY, at it last return 10
! 1886
This comet, Professor Mitchell. says, ''wii
soon commence 20 change direction, at first
slowly, afterxard more rapidly, rs seen from
the earth, when sweeping swiftly round the
sun it will regain those distant regions OF
space wherein a vast proportion OF Its orbit
! lies far beyond the reach OF telescope vision"
, lie further state:
! Ga the evening Of the 25.h of September,
the appearance Of the comet. in the great re
Hector Of the Cincinnati Observatory, was
ESPECIALLY interesting. The central portion.
I or nucleus, was examined With powers vary
1 Cd t,uo hun jrp1 r.
! out presenting any evidence of well defined
| planetary disc. 1t was brilliant glow OF
! light, darting and fAshinE forward 10 the
direction of the motion toward the sun, and
! leaving the region behind ia comparative
! ohscurlty. But the most wonderful physical
/ feature presented, was the portion OF a HCdr2y
! circular HeGuiOuS ring. with It's Vertex diTec-
ted toward the sun, the bright nucleus bein
/ 10 the centre, while the imperfeci ring swept
| m ire than half round the luminous CENTRE
/ This nebulous ring reese 0led those winch
sometimes escape rom steam.pIpe, but did
not exhibit the appearance which ought TO
! be presented by a hollow hemlspherlcal enve-
! lop" of nebulOus matter.
There was au evideat concentration OF
| light 10 the central portions OF the ring,
wnile 10 the case of hollow envelope, the
! brightest portion should be at the outer edge.
/ By micrometrIcal measurement, the distance
! from the central point to the circumference
OF the ring was found to be about nine thou.
| sand miles. This would give diameter OF
! eighteen thousand miles, IN case the ring was
entire. Similar measurements, made on the
evening of the Och OF September indicated
decided incre tse 10 the radius OF the ring,
which was now not less than twelve thousand
miles 10 iepgth. Ga the same evening |
! nat,ced tie iact that the luminous envelope
! did not blend itself into the head portion OF
! the tail, but appeared somewhat - penetrate
! into this nebu!nus mass, especially on tn
uper part presenting the appearance OF about
! 200 degrees of spiral. The tail on the 18th
was decidedly brighter and better defined on
! the upper than the lnwer portion, while on
| the evening of the Goth there was u much
nearer approach TO equality in brightness,
especially n ear the head of the comet
! Through the telescope, and near the head, tbs
! tail presented the appearance OF holio"
| nebulnus envelope, under the form ut para
! baloid Of revolution, the edges being brightest
and well defined. while there wasa manifest
fadirg away OF light towards the central re-
! glnns. Through The vast depths Of nebulous
matter composing this wonderful oTpendage,
! the faintpst te,eseoplc stars shore With und!-
rninished brightness.
| No one can gaze on this gigantic object, in
all Its misty splendOr, WITH u deep imprer-
! sion that the eye If resting on mass u! ne
buious matter. precisely such a. the nebulons
theory of La Place supposes TO have been the
prim0rdIa cOadltion OF our sun aud all Its
II tendunt planets, and from which chaotic
condition this beautiful system Of revoIring
words has been evoked by The action OF n
! single Law.
The only comet which has presented an
appearance resembling the one nU~vi'ible, IL
the , ne known as HALEY, Comet, ~ seen by
Sir William llcrschel and others IN It's return
IN 1886. There is Il marked difference be-
tween the two: That while toe env'!oie ct
Halley's Comet is described as hemispher-
ical hollow envelope, this shows more the
shape OF nnbulUus ring; there Is lalnt,
misty light, of irregu!a outline, bot not TO be
mistaken by even a casual observer"