The morning call. [volume] (San Francisco [Calif.]) 1878-1895, 1893-11-10
UNKNOWN BODIES
Professor Barnard Speaks
About Comets.
Many Theories i'm Regard to Them
Have Been Exploded Tails
10000, 900 Miles Long.

A highly interesting and Instructive lee
tnre on comets was delivered by Professor
Barnard Of the Lick Observatory at Cal
fornia-street Methodist Church last even
ing. In addition to an array of scientific
facts presented in a charming manner
Professor Barnard displayed some new
photographs on the steIeOpticOn screen.
He began with brief description of the
great comets which mad attracted most
attention.
Comets" said the speaker, 'are bodies
of gaseous matter, little drier toward the
middle than At the ouusides. AS this mid
die descends toward the sun it grows
brighter in the middle, and little star
like body appears and emitS jets OF bril-
liant matter. which streams out as
nebulous body and forms the tail. What
before was small in dimensions extends
to enormous sizes. stretching out
is we know not. 1t is supposed the tail is
composed of vapor. This we are not sure
of. The spectroscope does not reveal cor
rectly or satisfactorily what they are.
hydrocarbons are found In them. When
a comet passes between the earth and a
star you can see the star through the
comet. You think the star is in front
when it is known positively that the star
| is farther away than the comet. What the
| nucleus is composed of we know not. NO
astronomer has positively seen nucleus
| of a comet pass between the earth and a
| star SO it is not certain whether this
| center spot is transparent or Opaque. 1t IS
supposed that the nucleus is composed OF
| meteoric stone.
THE generally accepted theory is that
the sun has some repellant power which
repes the particles of the tail from 1t as
we'll as attracting the nucleus toward it.
| Conservation shows that this light in q
| ic rona n
| The tail of a comet would be very small
| indeed at 10000, 900 miles They extend
| from 80, OOO, 900 to 200. 900 Of miles.
1T is found that there are many comets
in connection with the orbits of the
planets Jupiter, Neptune. Saturn and
Uranus. Now there are other comets be-
yond the farthest planet, Indicating the
presence of an unseen planet off there In
space.
"In 1888 there was tremendous
| meteoric shower which startled the world.
1t was found in the Andes Humboldt had
! observed the same phenomenon, and, be-
| yond that it occurred at In tervals OF every
| thirty-three years for a thousand years.
| Connection between them and the presence
of comet was the Inference drawn.
Referring TO diagrams ON the canvas,
| Professor Barnard showed the three types
of tails, one of which having the specific
gravity of hydrogen was shot out straight
from the sun, the third and heaviest mad
specific gravity of vapor and curved
almost as short as circle. Drawings
of SpectrumS showing Hydrocarbons
in different comets were exhibited. Inc
influence of planet on changing COM
cts course was demonstrated by drawings
showing orbits and original lines. Had
this comet not come within the influence
of a iIanet it would have contynued on its
s raight way into Infinite space beyond the
stars. never to return" said the lecturer