Public ledger. [volume] (Memphis, Tenn.) 1865-1893, 1881-09-22
THE GREAT COMET OF 1881.
Unknown Heretofore, It Will Not
Return Fer Thousands Of
Years, II Ever.
P~bllaaolObia LEDGER

fhlAaelpnlA Leuger.I
Haverford College Observatory
Ninth Month. 3, 189l.-The grea
comet Comet B. 1881 beinb now, ex
cept in telescopes, a thing of the past
it may be we'll to gather the result
obtained by different scientific mel
from their studies Of it. The come
was seen by the naked eye in Soutl
America and Australia at least
month before it was observed here. |
was then q much fainter object thar
when it arrived at its perihelion
which was about coincident with th,
date of its northern discovery.
Good obseryatories exist at Rio
Janeiro, Cordova, in South America
and at Melborne and Sidney, in Aus,
tralia. The observations of it taken
in these places, in its Incipient stage,
while not revealing anything new as
regards its constitution or structure,
have been valuable in deducing the
form Of its orbit, and its identity with
previous comets. The northern OBJ
servations have been more varied and
productive. They may be divided
into III measurements Of position by
micrometer and transit instrument;
G2] drawings, showing its physical APP
pearance and changes, made by the
aid Of telescopes Ofgood defining pow.
err; l3l s~pectroscopic observations, for
the purpose of ascertaining its struc-
ture and chemical composition; [4]
photographs.
The first of these was for the pur-
pose of gaining data for a computation
Of its orbit. The results, so far as at
present deduced, shows that the
comet moves in a parabola, or in a
very much fattened elipse, and that
if it ever returns it will only he after
the lapse OF thousands ~ofyears. They
also show that if it has wei been here
before there is no record Of it so we'll
authenticated as to identify the two
objects. The bright comet Of 1907
has elements which very much resem
Bile those Of our recent visitor. But
Bessel, one of the most reliable and
careful of computOrs, gave it an orbit
which would not bring it around
again till after the lapse about 1900
years. and the points Of dissimilarity
are too great to be r~eeonciled; so that
the identity Of the two is certainly not
established.
1t has been suggested with great
FEASIBILITY that they were originally
connected, and that, as in the case Of
Biela's comet, in 1876, they have
parted company, and got so far sepa-
rated that one precedes the other by a
period of seventy-four years. The in
innate connection between meteors and
comets makes all kinds Of differences
from one to the other justi6able, and
it is certain that meteoric bodies chase
each other round and round in similar
orbits, aud hal they are probably
formed by the disruption of great
comets. Our comet may then be a
fractional part Of q still greater comet
which long ago was forced by some in.
ternal CONFUSION to shift for itself,
and which has since followed the
wake of its parent through space.
The second class of observations
we're those going into the details of
its physical appearance. They have
shown that violent forces have been
continually acting within. and render
the disruption theory probable. The
Cincinnati observers at one time an
%nounced its split. But by the time
other observers had the opportunity
to examine the difference was healed,
or the smaller member had faded
away, so as not to reach the dignity of
a separate comet. Great streams of
luminous gas would issue from the
nucleus. Envelopes would form them
selves around it and be dissipated.
The masses of haze surrounding it
would show exchanging shapes, aud
all appearances would indicate strong
forces operating within its mass, which
forces were stirred into life ty ap
proach to the sun and diminished by
recession. There have been made
some Of them published and some filed
away in observatory records-a num-
Der of drawings of its different appear
ances, which some day will be valu-
able foundations for theories concern.
ing its nature and structure.
The speotrospic observations have
given, in the words Of William Hug
gins, the great English authority in
this line Of work, the following re-
suits: Part Of the light from comets
is reflected solar light, and another
part is light of their own. The spec.
trum of this light shows the presence
in the comet of carbon, possibly in
combination with hydrogen" The
nucleus is probably solid and reflects
solar light, just rs the moon does,
while the streamers, the envelopes
and the tail are masses of carbon
gases, emitting light Of their own.
Besides proof Of the fact that comets
can be photographed, the results OBJ
tanned by the camera in photograph
ing the comet itself are not very yalu.
able. 1t would at drst appear that
the impression would be 0 aecu.
rate in its details than any drawing.
could possibly be-. And so it would il
the exposure could be only momen.
tary. But in the half hour or the
hour Of necessary exposure the details
Of the head may have greatly changed
The result is that no very definite
photographs of the outlines of the
head have been obtained, and thaI
the drawings will continue to be th,
reliable means Of knowing its appear
snce at any moment. But the photo
graphs Of the spectrum are Of tn,
highest utility, afFording the means o
leisurely and certainly determining tn
position Of bright lines and the char
acter Of the substances which producI
them, and enabling sp~ectroscopist
to compare with one another thei
! charts.
Such is q brief summary Of result
obtained from this productive comet
Never was one more carefully oh