New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1881-07-02
PHOTOGRAPHLNG THE COMETS SPECTRUM.

PROFESSOR DRAPER JUBILANT VALUE OF THIS
woRK-A CONTINUOUS SPECTRUM.
Professor Diapers face expressed his de-
light yesterday morning, than his Words when
he announced ubiantly that he had secured photo
graph of the spectrum of the comet Yes sir have
done it,, he said, rubbing his hands, and am both
surprised and delighted The experiment has never be-
fore been tried, and had little hope of success-cer-
tainly not OF such immediate success. had an ex-
posure of eighty five minutes, which brought to an
end by the glimmer of approaching dawn. The impress
sion, though narrow is distinct aud will all need
full purposes In fact, regard last night night Of
triumph"
The difficulties attending the photograrhing of the
comet itself multiplied by the interposition of the
specroscope, which diused still further the already
feeble light Professor Draper had, however, adj
used the object glass of his telescope that all the rays
of light were brought to focus the narrow slit OF
the spectroscope. The plate set very the slit
that, with the help of peculiar arrangement which
gives every beam its full effect but which Professor
Draper does not wish to describe until he has we'd it
further very good result reached The spectrum
OF the coma which the photograph IL directly above
that OF the nucleus, seems, Professor Draper says,
to be continuous, although vheI he examined 1t
the photograph was not yet dry. II there were any
lines at all, they must he thought be exceedingly faint.
The absence of banded spectrum 10 show that
the temperature of the comet is NOT high probably
not above the heat which can be prob the earth
by artificial means. The coma seems TO bc rapidly cool
ing it is fast subsing into the nucleus ls shape is
sui constantly changing: nj nrst IL rseiuDIed blrd
with spreading wings; afterwards IL took tie form of
the half section of wheel; then showed two forward
curvng with arc in front of them: and the
have disappeared leaving only faint In front
of the nucleus, with light misty appg between
Professor Diapers inference is that the volatile fluid
which blazed the coIsst approached the
| condensing again it reccdcs. The activity in the
head is continually growing less also, fact which ia
vors the same hypothesis.
The value of the photograph of the comet itself the
Professor says, arises from the fact that il gives
curate standard for future comparison very much
pcrlor to the Inaccurate drawings which have previously
been relied upon. The photograph of the spectrum has
n further value i'll that II shows elements and cOors
which the cannot discern in the visual spectrum
those OF other comets have DONE indicating that the tail
is composed of solid or liquid substances.
Would not the supp0sitiOn that the tail consists
matter i'll the fourth state explain the continuous spec
trum equally well u asked reporter OF THE TRIBUNE.
Well" the reply, =" the spectrum of the fourth
state OF matter does 10 Inc continuous but il has
not been thoroughly inNesgntcd matter in the fourth
produces phosphorescencc when lighted by
electricity for spocroscopc purposes Hence the spec
| trum of the matter itself is greatly obsciircd"
When the comet appeared Professor Draper had been
making preparations for six months to photograph the
neDua IN O1on. This IL delicate operation, and he
was well prepared for photographing the comet The
experiments upon the neba of Orion which have been
suspended during the period of the comet, will be
| sumcd after IL has disappeared from the sky.
Last night was very favorable for further obser-
Naons Professor Draper expected to continue his
| peInents upon the spectrum OF the comet