The Red Cloud chief., 1881-08-18
Photographing the Comet.

Prof. Draper's face expressed his de-
light yesterday morning. o than
his words, when he announced jubi-
lantly that he had secured a photograph
of the spectrum of the comet. ''Ie,
sir. | have done it," he said, rubbing
his hands. land am both surprised and
delighted. The experiment has never
before been tried. and | had little hope
of succesS-certainly not If such immc-
d ate success. | had an exposure of
cighty-.iye minutes. which wa brought
To- an end by the glimmer of approach
i'm dawn. the impression. though
narrow. is distinct, and will serve all
needfUl purposes. In fact, | regard
last night as a night of triumph"
The difficulties attending the photo
graphing oil the comet itself were null
tiplIed by the interposition OF the spec
troScope, which diilused still further the
already feeble light. Prof. Draper had,
however, so adjusted the object glass oi
his telescope that all the rays of light
were brought 20 a focus upon the mar
row slit OF the spcctroscope. The plate
was set very neal the slit, so that, with
the help OF 4 very peculiar arrangement
which gives every its full effect,
but which Prof. Draper does not wish 10
describe until he has proved it further.
Il very good result vas reached. The
spectrum of the coma, which on the
photograph is directly above that of the
neclcus, seems, Pro. Draper says, to
be continuous, although when he
examined it, the photograph was not
80 I.- .In-. tra-. an- tT.-.
at all. they must, he thought, be
exceedingly FAINT. The absence
OF a banded spectrum seems TO show
that the temperature Of the comet is
not very high, probably not above tie
heat which ear be produced IN the
earth by artificial mean. The on
seems to be rapidly cooling. as it Is fast
subs.ding into the nucleus. Its shape
is still constantly changing; at first ii
resembled 4 bird with spreading wings;
afterward it took the form of the half
section OF n wheel; then it showed two
forward curying arms with an arc IN
front of them; and now the arms have
disappeared. leaving only a faint arc in
front of the nucleus, with a light. misty
appearance between. Prof. Diapers
inference is that the volatile fluid which
blazed up as the come. approached the
sun is now condensing again rs ii re-
cedes. The activity in the head Is con-
tinually growing less also. a fact which
favors the same hypothesis
The value of the photograph of the
comet itself. the Professor SAYS, arises
from the TACT that it gives an accurate
81 a rta ri for fnrnrn HAnsfaaFT.nn garr
much superior to the inaccurate draw
ings which have previously been relied
upon. The photograph of the spectrum
has a further value IN that il shows eIe-
ments and coiors which the eye cannot
discern in the visual spectrum The
tail of this comet shows = on
tinuouS spectrum, as those OF
other comet, have done. indicating
that the tail is composed of solid or
liquid substances.
Would not the suppos!tion that tho
tail consists of matter In the fourth
state explain the continuous spectrum
equally wcil:?' asked a reporter of the
Tribune.
Well" was the reply, the spectrum
of the fourth state oil matter does ap-
pear to be continuous. but it has lot
been thoroughly investigated: matter
in the fourth state can only be exam
ined in a glass tube, which always pro-
duces 4 green phosphorescence when
lighted by electricity for s~pectroscopie
purposes. Hence the spectrum of the
matter itself is greatly obscUred."
When the comet appeared Prof
Draper had been making Preparations
for six months TO photograph the neb-
ula in Orion This is n very delicate
operation, and he vas vel prepared
for photogrsphing the comet The ex-
permert; upon The nebuia of Orion.
which haEe been suspended during the
period o. the comst, viii be resumed
after it has disappeared from the sky
y. Y. Tri5zRe-