Bismarck weekly tribune. [volume] (Bismarck, Dakota [N.D.]) 1884-1943, 1895-02-01
A STUDY OF THE sun.
A FASClNA ING RECREATION WHICH
.' ANY ONE MAY ENJOY.

~ 'o0'NH wv btOtN SIIlS
$685.. ANY ONE MAY ENJOY.
A Method of Getting q Perfectly Pure
Beam For Inspection-A Lesson In As
tronony Couched In Simple Terms.
Every day a royal presence, attended by
numerous unseen courtiers, sweeps across
the sky. The sun looks us so boldly in the
lace that we are compelled to veil ourselves
from his Accusing gaze. Let us commence
our new studies by contemplating his at.
Effectiveness.
A piece OF well smoked glass will give
US good service. If this be covered with
another piece, with strips of paper at the
edges to separate them and prevent rub
bling, and other mucilaged strips to bind
the outer edges, we shall have a respecta-
bic and lasting astronomical instrument.
The eye may now examine the dazzling
orb without danger, and it will discover
q disk which is apparently no larger thar
that of the full moon, but the fact that
the sur is about 400 times farther away
accounts for the resemblance in size. But
the disk is not all of the immense world,
for a very important envelope of vast di-
mansions is invisible except to special in.
struments. The limb of the sun is seen to
be not quite SO bright as the central por.
tions, because the light from it has to
penetrate a greater depth of atmosphere.
Occasionally we see a ''spot" upon the
solar surface, in which case it must be
very largo, but if we are fortunate enough
to have access to even a small spyglass We
shall many times SEQ spots. There are
years when the spots are very numerous
(thc writer counted 1863 one day and more
than 800 on Il day in 1889, and years
when non is seen for months, and this
appears to be governed by a period" of
about II years.
II we use Il telescope with our smoked
glass, the spectacle will be %curiously in
tercsting, for the object glass-a very large
e~ye-gathers many rays Of light and bends
them to a focus, producing a magni1icd
image which is yet more enlarged by the
eyepieco, which is a microscope. Now,
the very grain Of tho sun, so to speak, is
visible, the surface being completely flockeu
with gray white matter, while here and
thcrehuge masses of white p%rotrudc. These
latter arc called facul;c and arc usually
associated with the spots which arc do
pressiOns in the surface-deep, dark cavi-
ties, but dark only as contrasted with the
shining regions, for they arc brighter than
the calcium light. Very recently the writ
er measured a large group and found that
it occupied an area of more han 100, 600
miles in length and about threc-fourths as
wide, into which could be cast 100 carths
without crowding them. Still larger
groups have sometimes been noticed.
Watching the spots from day to day re-
veals tho time Of revolution of tho sun
upon it's axis, about 25 days, which means
that one day on the sun is as long as 25
of ours.
AS yot the sun has not yielded the secret
of its composition, and the telescope, I'M
aided, is inadequate to solve the mystery.
Perhaps in childhood wo beguilcd hours
of church service, which were a trife
wearisome to little ones, by noticing the
play Of color in the clusters" which hung
in profusion from tho old fashioned lamps.
How little we dreamed that the sun was
whispering through this simple medium
Ineligible messages Of very high impor-
lance, for this three faced form of glass is
called a prism, the change Of direction of
objects viewed through it being due to the
bending (refraction) of tho rays of light
passing through it, and the color fringe
along the ed ges of the images the primary
rays of which white light is composed,
which is easily proved by passing the col
ored rays through another prism, when
they form u beam Of white light once
more.
The same color band, or spectrum, is
shown by n grating of parallel wires
strung in a frame, or by a close grained
feather, or even by the eyelashcs when the
eye is half closed.
But WI can easily improve upon these
primitive instruments by employing Il
series Of pris,ns of fine construction or a
grating produced by ruling lines with IL
diamond upon IL piece of perfectly flat and
highly polished speculum metal.
To get IL perfectly pure beam for inspcc-
ton NC let the telescope image of the sun
fall upon Il delicate slit in a metal plate,
which is in the focus of the object glass of
a !ittlo telescope, whose duty it is to mako
parallel the rays to be examined, and
which sends them through the series OF
prisms referred to or causes them to fall
upon a grating. In either case they arc
viewed by another little telescope, and the
beam of sunlight tells its story in IL mag,
nificent spectrum, far exceeding the rarrs,
touches of world renowned artists.
Now for the precious secret! The beau.
tiful color band is threaded with thousands
of slender dark lines, which correspond
with the bright lines, which are the sign
manual of metals in Il glowing state, and
we need only to put Il pinch Of salt in the
flame of a candle and let the light fall
alongside tho suns image on tho slit,
when there will be W o spectra, side by
side, and the two bright yellow lines Of
sodium will exactly coincide with two
black lines in tho orange of the solar spec.
trum, and tho browning proof appears
when the calcium light is permitted to
shine through the candle fame, instantly
turning the bright lines to dark ones. So
with tho lines of other metals. We have
learned from the suns own messages, aft
er a journey Of 90, 600, 600 miles, that it is
a gaseous body; that many of tho metals
of earth are vaporized in it's awful tenn.
peraturc, and that the surface is probably
y shell of luminous clouds surrounded by
an "atlmosphere" of gases thousands of
miles deep, out of which squirt for hun
dreds Of thousands of miles, with a speed
in contrast with which the movement Of
whirlwinds on earth is IL dead calm, jets of