Western sentinel. [volume] (Winston [i.e. Winston-Salem], N.C.) 1856-1886, 1879-06-19
Spots OH the SUN.

dt ION OI tie SGDlGCt.
Spots OH the SUN.
THEY WILL BE NUMEROUS THE NEXT TWO
TEARs-A NUMBER NOW VISIBLE
| The period is approaching when
she greatest number of spots appear
on the solar surface, Even at the
present time several are visible,
and some of them of considerable
size. A number of facts seem to
warrant the opinion of perhaps a
majority of physicists that the
changes on the disc of the central
luminary which the spots show to
DC taking place influence many
phenomena. The variations, there
fore, from uniform brightness on
the great orb OF day are at present
watched with an interest which was
unknown i'll the infancy of optical
and astronomical science. The dis.
covery of the checkered physlogno~
my of the solar ORD is due to Cali
leo, though accounts of variations
in the SUMS light date as far back
as the reign of Augustus Cesar
In April, 1911 soor after the in
vention of the telescope, spots were
observed by the Florentine astrono
mer and nearly at the same time by
Schrciner, a German Jesuit, and
! Fabricius, the friend of Kepler.-
Being unacquainted with any means
Of diminishing the intense glare the
inst telescopists were obliged to
make their observations through
thin clouds or when the sun was
near the horizon. The blindness
which elnbittered the latter days of
Galileo was no doubt caused by
watching the sun spots, and the
elder uerschel lost one of his eyes
in consequence of his close study of
solar phenom ena.
1t has been found from the ex-
animation of a long series of obser-
vaticns that the times or the greatest
number Of spots recur in about
eleven years. The last took place
in the summer of 1871 In that
year and the preceding they were
frequently observed and measure
ments made of their size, at the
Observatory in Philadelphia. On
two occasions spot was observed
with the naked eve which was at
least $4,000 miles in diameter. In
1889 spots of $4,000 and even of
"A 600 miles are recorded. In 1916
there were seen on several occasions
without the aid of the telescope.
The readiest way of observing
the spots is to receive the image of
the sun either on a screen or paper
marked by perpendicular and hori-
zontal lines of an equal distance
from each other. Not only the
outlines of the spot, but also its
relative size can thus be easily
traced. Many other theories have
been brought forward to account
for the spots on the solar surface,
especially since the rose-colored
flames which appear during a total
eclipse of that luminary have been
shown to be caused by hydrogen
gas. But with the exception of this
fact and the manifest effects Of cy-
clcne-like waves which rise and
produce disturbances in portions OF
4 its disc, the true causes of the
changes or the suns surface, with
the exception of those produced by
some of the planets, as we'll as the
sources Of its heat and light, arc
unknown. Observations of the
spots now appearing, and which
will become more numerous during
the next two years, may enable
physicists to determine many ques-
tions connected with the central
luminary which arc now unanswer-
: cd. The elder Herschel supposed
that the average temperature Of
years III which a large number ot
spots appear on the solar surface is
generally lower. This has not been
fully proved, yet the summer o.
1916, so remarkable for large spots
was the coolest on record in the
United States.
A Good Rule.