The morning call., 1893-11-26
STARS ANALYZED.
Their Composition Found
by Comparison.
Professor Campbell OF the Lick OBJ
servatory Speaks About Won
ders of the Speetroscope.

The Astronomical Society of the Pacific
met at the Chabot Observatory, Oakland,
last evening and elected the following
named ladies and gentlemen as members
OF the society: Walter Camp, Philadel-
phia; Father Dienelt, Loda, H.; Miss
Elsie Hadley, State Normal School, Valley
City. n. D.; Andrew P. Henkel. Cincin-
natl; DR.. S. P. Langley. director Smith
sonian Institution. Washington, d. c.;
Professor f. 2. Leavenworth, University
Of Minnesota. Minneapolis; Sam c. Phipps,
Milibrae. CAL; j ohm j. Pierrepont. Brook
lyn, n. Y; C. A. Spreckes. Mrs. c. A.
Spreckels, Rudolph Spreckels, San Fran
cisco; Miss Gertrude Stanford, Oakland
j. W. Ward. Sydney, n. S. W.; Mrs. E.
Nj. White. Framingham. Mass.
Professor Campbell of the Lick Obser-
vatory delivered a lecture on 1.-The Stars
With Bright Lines in Their Spectra." As
a preface he said that q little over half a
century ago noted French astronomer re-
corded it as his opinion that men would
never be able to know the chemical consti-
tuition OF the stars, and yet the spectrum
has not only given this knowledge but has
done for astronomy what Darwin did fur
the theory OF evolution. Astronomers are
now almost wholly interested In the rela-
another. As light comes to the earth with
all the cOlors of the rainbow. he said. II
was impossible to curve lens so as to bring
all the light passing through to per-
feet focus. In other words, heavenly
bodies are seen in the great telescopes sur
rounded by blue and violet light. but for
which astronomers could form some estl-
mate of the stars. To obviate this condi-
tion the image is not only passed through
the telescope, but through spectroscope.
In explaining the fundamental theory
OF the spectroscope Professor Campbell
gave an apt illustration glow of CAL
cum light through speetroscope gives a
continuous spectrum, but il the flame of a
gas-alcohol lamp for example-be viewed
through the instrument isolated light lines
are seen on the spectrum. 1t Is known
that sodium exists in the gaseous hame
and that its presence causes these bright
lines, which are also often present IN the
sspectra of bright stars. SO when these
lines are observed In the sun or stars OF
nebul8 astronomers know that sodium
exists in gaseous form.
The spectra of various stars ann nebulae
we're shown in photographs by stereopti-
con lantern and their lines were ex-
planned.
From certain dark lines on the spec
trum. said the professor, we know there
is sodium, magnesium and hydrogen sur
rounding the sun We have been able to
prove that nearly all chemical elements oil
1ne 1ne earth are around the sun In vap0r.
The lighter stars have hydrogen line
The spectra of stars differ radically, TAX.
ing the hydrogen line as q basis. In
Sirius there are heavy hydrogen lines
and also dark lines, which are due to the
presence of iron.''
Turning to the evolution aspect the pro-
lessor demonstrated that the spectrum in.
dicates the age 10 q degree. Astronomers
know that stars are formed largely by the
gathering of nebulous bodies. In older
stars there are many dark lines. showing
absorption. while in stars recently discov.
cred the lines were few in comparison.
Regarding nebula he said it was found