Daily Republican., 1881-06-27
WATCHING THE COMET.
ODservationsby Professor Draper.
He succeeds i'm Obtaining Better
PhOtogrsphs-What he Expecs.
to Accomplish Further.

: PhOtogrsphs-What he Expects
q to Accomplish Further.
g Professor Draper OF New York suc.
ceeded once more yesterday morning i'm
r photOgraphing the comet. Two i'm
pressions were obtained, one of which
i. is of the size as it appears to the eve.
while the other is enlarged fifteen times.
The smaller image, which is the more
distinct, shows. the nucleus and coma.
with a portion of the tail to the length
of five or six degrees. The enlarged
figure, though fainter, reveals the shape
of the coma, which, flowing outward
from che Nucleus on both sides, gives
the comet much the appearance Of %.
bird with wings oIItspread.,
One professor says:
'yThe analysis of the substance of the
COMA, by means Of the spectroscope,
will be of even more scientific moment
than the photographs. The report from
the Harvard College Observatory that
the nuclSus gives a continuous spec
trum merely shows that the Duclells is
q soliG or liquid body, and therefore
cannot be analyzed. The coma, how
ever, is composed of gas, and will
| INi"SitiOic ICh't IeoClI W bDO ttSpS OI bUt1
spectruIE analysis. The spectrum of d
comet has never been satisfactorily OBJ
tained, bAt such i'm mperfect results AZ
have been obtained iplicate the proba-
Bile presence Of sSme compound Of car
bon in the coma and tail. The nucleus
OF Coggia's come5, which appeared in
1874, gave a continuous specJrum, but
the coma showed three bands which
resemoed very much those ofthe hydro
carbC1s.
The spectrum Of carbon itsels indeed,
is not very well understood, :; h,at the
imperfect analyses Of comets which
have heretofore been obtained show a
marked resemblance 20 that Of an cleo
tric spark discharged in 0lstiant gas,
which consists Of hydrogen and carbon.
AS the SpectrOSCCpe has been mach i'm
proved, look tor important results
from its application to this, she bright
EST comet since the appearance Of Dom
ati'S in 1850.
In answer TO an interrogatory from IL
reporter Professor Draper said
A comets tail is Cne OF the strangest
things i'll the universe. ThOugh mil
lions Of miles in leugth, guivsring,
billowy trem0r. such as the aurora bore
aliS sometimes shows is often seen run
ming IN % few seconds from ono end to
the other. The well known la,waof mo-
ton are inadequate to account for such
- phenomenon Tie behavior of the
tail is in other respects also very singu-
lar. 1t always, for example, points di
rectly away from the centre Of attraC-
tiou, following after the nucleus ia it's
approach TO perhelion; and as the comet
sweeps around the sun it whisks
SQddtntly about, SO as TO Keep the
solid part always between itself
and the sun, finally going III
advance as the comet rttSdes.
This popularity has given rise to the
speculation that the tail might be mere
ly kind of luminous shadow, like the
whitsh light that is sometimes throw
across the sky by the rays Of the sun
shining Tough a cloud. 70 test this
theory Professor Tyndall tried some ex-
periments by passing a stream of light
through certain gaseous or li1uid suh-
stances, but the hypothesis ). sA >,
tenable. Aside from other considef1S'
tious, the tail OF this cyfnet is convex
toward the east. IL Can hardly be IL
negative shadow, therefore, as shad-
OWS are not curved. IL IS easier TO say
what the tail is not than what it is.
1t will be visible for ID good while
perhaps for many weeks. 1t will not
set below the horizon, but may be seen.
i'll fair sky from dark to dawn. In
the daytime it is nearly overhead. l.
have no data tor determining whether
this is anew cOmst or a familiar one;
ii used my time to observe its motions
| should have had mole lett for agGer-
tanning its shape and composition.
The comet was plainly seen from 3
o'clock on until midnight but after nine
o'clock the sky became obscured with
clouds and the comet was only visible
at times, but many spent the night un-
tiHthiS morning set III watching for it
The professor thinks there must have
been some mistake III the report that the
comet was approaching the sun. ''lt is
certainly recediug. 1t is gradually
rising above the horizon and approach
ing the North Star, about which, with
The rest of the heavenly bodies, it ap-
pears to revolve. 1t will continue to
lraw nearer to he pole, growing fainter
md fainter until it disappears. For 70
ew days, how ever, it may possibly in-
,reaSc in brightness. 1t moves very
asst at present, passing over space OF
bout ~ every day.