The daily intelligencer. [volume] (Seattle, Wash. Territory [i.e. Wash.]) 1876-1881, 1881-07-16
DAILY INfELLIGENCER.
Saturday, July 16, 1881.


ton Camelus. said Prof Henry Draper
in Dobb's Ferry yesterday. and is rush
ing along at the pace of half Q million
miles day. Rapid changes are going
on both IN the coma and in the nucleus.
When first saw the comet q week ago
the coma curved out and on each side
Of the nucleus in the attitude of fly
ing bird. But last night the wings
had Topped forward, or rather back
ward, toward the sun. Another re-
msrkable phenomenoa was that Q large
part Of the coma has settled upon the
nucleus. This 10 accounted for easily ?.
You would naturally and truthfully
presume that as the comet retreats from
the sun it would lose its heat originslly
given to it by the sun. The coma is
undoubtedly volatile. and as the heat
of the nucleus decreases | should ex-
pect that the coma would become less
in volume and fainter in appearance.
Such is the fact.
Another curious fact. As l looked
at the nucleus it flashed out TO an i'm.
meDse distance on the side toward the
sun. Then / remembered that the
great Donsti comet in 1853 did the
same thing. and that comet also gave a
thrill or shake all along its tail at the
instant when the nucleus burst out to-
ward tine sun. i looked anxiousIy for
similar thrill in this comets tail, but
saw none. The nucleus is sphere no
longer, but is more oblong.'
Have You obtained another photoA
graphr
Yes; last night tried to seize the
comets tail. / knew that the comet is
getting among millions of stars, and l
wanted TO see whether the tail would
prove an obstruction to the rays of
starlight coming through it to the
earth. l wanted to quiet Marx Twain's
fears and relieve him from his gener-
Gus self-imposed-task of standing on
his house top with pole to fend off
the comets tail if it should whisk
around this way. He can climb down
now, for the stars showed very wildly
through the tail. By the way. q curl
ons thing happened in taking the plate.
| exposed the plate to the tail of the
comet for three hours. The plate was
so sensitive that diffused starlight stain.
ed it. Well, when / was through the
experiment and had developed the neg
alive / started and thought that it had
been ruined. 1t looked as though q
shaggy substance had been passed over
1t, leaving innumerable straight lines
ell in the same direction. Then l
laughed aloud at my blunder. The
double motion Of the telescope and
,, plate, one motion to counteract the
earth's motion, and another that of the
comet. had left the stars motions to
for themselves. And they had pur-
sued their own motion across the plate,
leaving little photographs of them
selves at every instant, and thus each
one formed continuous line. The
photograph is vivid, and is as good as
can be taken. 1t is 8 degrees in length.
The eastern or convex side is brighter
than the concave side, which has be-
come more filmy and delicate
Have you aimed the spectroscope at
the visitor yet to see whether anything
can be learned of its composition?'
Yes, and am going to keep doing
it as long as the comet can be seen.
My object is to see if the nucleus gives
any but continuous spectrum. Sun
light does not give continuous spec
tram, but is broken up with lines which
show the presence of many minerals
burning. Only a solid, or liquid heat
ed to @ vigorous condition. gives a
continuous spectrum. This is what the
apocfroaoOra aho-a1 nhn, d;rooto1 a.
the nucleus. but in such an object as
comet O number of observations must
be made to arrive at truth. So looked
for absorption lines which are given
by incandescent matter shining through
gas. II I had got the lines 1 would
have been sure of gas around the nu-
cleus; but the spectrum was continu-
Gus.
MY second object continued Prof
Draper, was to see whether the tail
shone by light reflected from the sun.
Now, sunlight. even il reflected from
the moon or stars, gives lines in the
spectrum. Therefore the tail shines
with its own light.
My third object was to examine the
coma and see whether il is giving out
bright bands in its spectrum. Bright
bands are due when seen in the spec.
trum. to compounds of different chemi.
cal elements; and lines. to distinct ele-
ments. In q spectrum of the electric
incandescendest light there are bands,
and they are broken up. showing q
mixture Of hydrogen. In the spectrum
OF the coma of Goggles comet the
bright lines indicated the presence of
hydro carbon. In the coma of this
comet. however. the bands are much
softened down by the brilliant continu-
Gus spectrum of the tail
What, then. in your opinion, is the
comet made Off
The nucleus is either solid or LIQUID.
probably solid and mineral. heated by
contact with the sun to just the degree
OF heat that ifyou heated it more il
would liquify. do not believe that
the nucleus is any hotter than you
could heat q mineral on earth. To-
gether with mineral is probably some
volatile fluid like nsphtha. Our sun
falls in with this huge ball wandering
IN space and attracts it. The comet
rushes toward it and the na2htha heats
up on the side toward the sun and sets
the whole affair on FIRE. The tail that
it throws off take to be particles
- 1T