New-York tribune. [volume] (New York [N.Y.]) 1866-1924, 1881-07-09
COMPOSITION OF THE COMET
PROFESSOR DIArHH's OBSERVATIONS COMMUTE
HIS srCOEhsFuL rnOInHRArIIs

PROFESSOR DEArHEs OBSERVATIONS CONTINUTD-
HIS SUCCESSFUL rHoToGRArns.
though the public interest in Professor Diapers
observations of the comet has been necessarily
suspended during the past few days h. has pushed
his experiments steadily forward in his observatory
at Hastings. His anxiety for the Presidents safety
Is however, none the less deep ON that account and
he expressed his concern, particularly Yesterday
afternoon, TO know whether any part of the Prcsi-
dents clothing had been carried into the wound
" | have cut out the shrcds of clothing" he said
from many a bullet wound during my practice as
surgeon in the army, and ALWAYS regarded that ~
one of the first considerations. However, We may
rest secure. the President il in the most sAful
hands that the country aforlsr
Since last Saturday Professor Draper has photo
graphed the the spectrum Of the comet three times
SO that he now has four plates showing the analvss
vi 'io ilRht' 'h" oI the impressions represents
exposure of DDS minutes, or nearly fonr hours and
~ very satisfactory, showing the advantages of The
improved form of spectroscopc which Dr. Draner
employs in dealing with the stars and which
though difficult to gives the best of results.
Each OF the photographs has a reference spectrum
above IT, taken at The Same time that Is to say the
spectrum of some other ccos ia body with which it
can he compared. Tho lumnary used in this in
stance Tor reference is the star Vega the brightest
men4ber of the constcl ton Of the Iyre Professor
Draper has also in his possession the spcctrum of
Nega-and that Of tho sun upon one plate taken with
the same spectroscopc that he now uses Thus he is
enabled to compare the comet directly with the sun
ne comet ana the sun cannot be photographed, of
course Mt one time, but the star Vega and tho
planet Jupiter were submitted to the spectroscopc
together.
In the spectrum Of the comet" said Dr. Draper
on Thursday, there is great band in the ultru-
violet region beyond the line II. This morning |
brought the spcctroscopc with me to the city and
have taken photographs of the spectrum of tho
electric arc with it. Tho electric arc contains car
Don; not, III all probability, the pure element of
carbon Voiatiilzed, but some compound Of carbon
most likely hydro-carboD. The spectrum of the
electric or votac arc shows strong band il the ultra
violet region due to the presence of this carbon or
carbon-compound. This spectrum mean to compare
win thtl ol the comet to whether the bands in
the ultraviolet region correspond in the two If
thcy 90, the presence of form of carbon in the
comet VIII be demonstrated. Ny impression at
present Is that the ultraviolet spectrum of the
comet does prove that it contains carbon but can
not speak with certainty until after have made
'noie careful measurements Of the photographs. At
all eVehts, my experiments sett the question:
rroiessor Draper had not observed the alleged
division of the comet into two paris bnt tboucht il
not unlikely. " 1t is not easy" he said to under
s,su Why comet should split in two hut It is we'll
known 'hat Biea's comet did so. We should at least
expect the division TO take place while the comet is
nearest TO the sun, but then il il quite possible that
spnt may nave occurred Mt that time which is
now ior Inc nrst time becoming visible But why
MY experiments SO far have confirmed nv opinion
sna. u comet consists of porous, bibulous sub
sa' i comDhed or saturated with volatile fluid
III the nature OF REFRIGERATION, such, for example,
as naphtha. IL is easy to see that if "A brckbat
were stepped IN naphtha and hurled toward the
IL would burst into n blaze very much as n comet
seems TO DO. Indeed if somebody will only increase
Inc range OF our ordnance, don't why
shouidht traln howitzer toward the sum- and have
Htte comet whenever we please If the proectile is
only MADE OF hre-brck, il Ought 10 resist the heat
thht TINS comet undergocs for notwithstanding
sore Opinions that have been expressed 10 the
iary, sun think that its Temperature. com
pared with that of the stars, is low"
oo; WI you Try to photograph the comet itself