The morning news. [volume] (Savannah, Ga.) 1887-1900, 1899-03-24
CARBON VAPOR IN THE SUN
An Exquisite Bit of Astronomical
OBSERVATION.
From the New York Tribune.

from the New York Tribune.
dainty piece of spectrosoopic work by
Prof. George E. Hale, director of the
Yerkes Observatory. has recently come to
light, although it was performed several
months ago, In the solar spectrum there
were long ago recognized bands that in
dictated the presence of carbon. But
whether that substance was in the suns
atmosphere or in the earth's. and. if the
former supposition were correct, in what
part of the immense gaseous envelope of
the ORB OF day, no one dared to say with
confidence.
1t mas been suggested to be sure, that
the dazzling brilliance of the sun is due
to minute PARTICLES of solid carbon float
ing in that luminous cloud she'll the pho
tosphere. But this theory, while having
an air of probability. has not vet received
substantial demonstration. Until Prof
Hale took up the investigation the nearest
approach to evidence that there is car
bon in the sun at all was the indefinite
announcement, in reports of the eclipse
OF January, 1898, that in some of the pho
tographs taken of spectra of the append
ages OF the sun carbon bands had been
detected
What Prof. Hale has done is to locate
the carbon with precision, and thus TO es-
u.
element of his success was the size of his
new telescope. While he was still living
an chicago, and conducting now famous
work a his private observatory, he had
a Pinch refractor, which gave him an
image, at the eye-piece, only two inches
in diameter But with the immense ~
inch refractor at Williams Bay he is able
to get 7-inch image. Setting the slit
OF his spectroscope on the very edge of
a co hA III
dreds of lines, representing the gaseous
layer known as the chromosphere and ly-
ing just above the photosphere. Among
these he found considerable number that
had never before been catalogued But
he also noticed that a certain shaded
band, indicating carbon and situated near
the small b. line, was beautifully reveal
ed 1t was resolved into its component
lines, spaced from each other in that Won
derfuily rhythmical manner that is stin
a puzzle to the expert physicist. The
clearness with which these lines were de-
fined had never before been approached.
new and decisive experiment was now
found to be feasible. By a slight change
in adjustment the slit of the spectroscope
was alternately made 20 cover the edge
| OF the photosphere-what is to ordinary
| people the hard, substantial disk of the
| sun-and then the atmospheric layer just
| oOSFS Ab-oOHlGlllllAS never seen without
| Instrumental aid This shifting of the in
strument was attended with a surious
| change in the carbon lines. At one mo-
| ment they were bright and at another they
were dark.
Every spectroscopist knows that when
| an incandescent gas is viewed directly it
| gives bright-line spectrum, and when an
other source of light is placed behind it,
so as 10 allow a different radiance to
chi
| lines will be dark. IL was thus demon
| strated that the carbon existed in the form
of vapor in the chromopheric layer. and
that when only this layer was covered
| by the slit of the spectroscope bright lines
| were visible. But as soon as the slit was
| placed over the photosphere the light of
the latter, coming through the chrome
| sphere. would produce black lines.
After having settled the fact that the
carbon which produces the familiar mark
| ings is in the solar atmosphere, Prof Hale
undertook to ascertain its exact position
therein. He then found that it was in
the lowest part of the chromosphere.
| When that particular envelope was in an
undisturbed condition the carbon came
| first, iron next and then sodium. magne-
| stun, helum. calcium and hydrogen. But
| when an eruption occurred, tossing the
| chromosphere up into enormous pillows
and destroying all semblance of definite
| arrangement, the position was not we'll de-
fined.
Prof. Hale Is satisfied that the carbon
| layer is a thin one, and that normally it
| lies down within 500 miles of the suns
| surface-a conclusion that harmonizes
well with the notion that the glow Of the
| philosophers emanates chiefly from parti-
| cles of solid carbon suspended therein. For
| it is highly probable that the intense heat
| of the sun-estimated by some scientists
! at 5000 degrees centrigrade-would vapo-
rize a little of the carbon in the luminous
| cloud shell and send it up into the chro-
mosphere.
| II was only under the most favorable
| conditions of terrestrial atmosphere and
| other related factors that Prof Hale could
| make these observations. The delicacy of
/ the work shown by this fact. Measuring
| sizes and distances with a micrometer re-
| ouires the utmost stability of apparatus
| and steadiness of atmosphere. Yet so
| firmly mounted is the immense refractor
| at Williams bay that Prof. Barnard can
| perform this task while the driving clock
| is being wound. But when that operation
| was performed in the middle of Prof.
| Hale's examination of the spectrum of the
| chromosphere, the carbon lines disappear
| ed in an instant. 1t is possible that the
great thirty-six inch glass of the Lick
| Observatory, in California, may be able
| to show these lines well defined but with
that exception it is not likely that any
| other telescope in the world will admit of
| an observation such as the talented young
| director of the Yerkes Observatory has
| CO c1n N rpDOTfiOO