Savannah courier. (Savannah, Tenn.) 1885-1979, 1890-03-20
THE SUMS CYCLONES.
Disturbances of the Solar Atmosphere tho
Cause of sun Spots.

Cause of sun Spots.
Prof. Searle's lecture at the Catholic
University on the physical constitution
of the sun gave some interesting infor-
nation respecting the sun spots. Cali
ieo, he said, first saw the sun spots with
the telescope. Sometimes they can be
seen with the naked eye as the sun is
setting, but only rarely. If we take an
ordinary opera-glass, taking care to pro-
tect our eyes with piece of smoked
glass, it is probable that we can see one
or two at almost any time.
The spots are composed OF dark por-
tion called the umbra, and a surround
ing lighter portion called the penum-
bra They are irregular in shape and
not round, as they would appear through
the opera-glass. If we look through the
telescope on two successive days we will
see that the spots have changed their
size and position. They are sometimes
smaller and sometimes larger, and it
often happens that new ones have ap-
peared that we did not see before. But
it will be found that all have moved
considerably to the right, and this will
be very noticeable every day.
1t takes spot on an average about
| twelve and one-half days to cross over
from one side to the other. They seem
to move slowly near the edges and more
rapidly as they reach the sun. In the
center they appear broader and more
round than at the edges, where they
are foreshortened and become elliptical.
From these and other facts we conclude
that the sun is, like the earth, globe
revolving around central axis, but it
takes the sun twenty-five days to make
a revolution. Sometimes the spot that
we have already observed will reappear
at the end of twenty-five days from its
first appearance, but ordinarily they do
not live as long as that. The spots are
found to occur only in a belt each side
of the equator. They are in a continual
state of fux and change, not only in
themselves, but in relation to each
other, They seem like the clouds in
our air. The penumbra consists of rays
or cylinders radiating from the umbra
Not only do the spots become elliptical
as they approach the edge, but the UNI
bra is noticed to approach the inner side
of the spot and sometimes to disappear
Often there is a spiral arrangement
of the rays asothey approach indicat
ing a whirlpool motion. The Who'll,
character of the umbra indicates tina
they are holes into which the surround
ing water is being drawn with wil(
velocity. 1t is supposed that tn,
bright surface of the sun which we Sc,
is a luminous cloudy envelope or gas
eous atmosphere, and that the spots ar
centers of tremendous solar cyclone
compared with which the widest tor
nadoes that visit our earth are no NOR
than the slightest breathings of child
A velocity has been observed in thei
movement as great as $50 miles sec
ond. When we consider the very enor
nous masses of matter, sometimes tel
or even 100 times as great as the who'll
mass of the earth, which are projecte
upward in that way or thrown to on
side or the other or thrust down int
the great cavities this awful manifesto
tion of power gives us a better idea O
what such velocity means and of tn
tremendous forces which work in it
production.
There is still some dispute about tn
periodicity of the spots. The extraol
dinary weather this winter has bee
supposed to be due to the absence c
sun spots, but it is doubtful If any rei
connection could be demonstrated
Every eleven years there is time whe
we have maximum of sun spots, an
l half way between there is a minimum
9 of spots. This recurrence Of periods
t activity has been remarked ever sine
the spots have been under observation
. Undoubtedly the spots have some COZ
u nection with the magnetic phenomer
Q of the earth, and especially with the a
: rora, and through these they may hay
some connection with the weather..
Washington Star.