Evening star. [volume] (Washington, D.C.) 1854-1972, 1923-05-20


of the aurora borealis. Telephone
and telegraphic disturbances were
such as to cripple communicates.
both on land and sea. When the sun
spots moved with the rotation of the
sun, the disturbances passed.
These spots were ahead of time. for
astronomical records show that the
years. Previous to their last appear
ance. they had come into view as
well as action in August, 1917, when
the Naval Observatory took photo
graphs which disclosed that there
was large sun spot group, spread
ing over about $4,000 miles.
While the appearance of these spots
was not without precedent, 1t was
nevertheless remarkable. The pic
lures taken of them were called pho
toheliographs Prof. Peters at that
time said.
The maximum period between the
maximum outbursts of solar spots Is
about eleven and .one-tenth years.
The last maximum period was In
1917. The minimum cycle. when the
spots would not amount to much,
would be in 1928.
So IL there has not been any change
in the time schedule. the sun spots
may appear this year. 1t will be re-
called that European countries were
affected in manner similar to this
nation. and while In France there
"a 49, = H.
telegraph and telephone wires were
affected. While certain officials OF
the government were OF the opinion
that the sun spots had no effect on
the condition of the weather. scien-
lists in some parts OF the world
held different view. Whether or not
they did affect the weather, the fact
remains that during the period OF
the visits of the sun spots the world
suffered from severe electrical dis
turbances.
There is interest in the way Prof.
Peters prepared for his evenings
| work--not the night when visitors
are there. for he does not consider
that work. 1t is more in the nature
explain to folks what he knows about
/ the inhabitants of the sky. In this
respect. all the officials of the OBJ
servatory. from Supt. MacDougal
down to the messengers, are courte-
Gus to visitors. They are men that
enjoy their work and they are con-
siderate of others.
This time we will not visit the
dome that houses the "twelve-inch,"
but will go down to the edge of the
grounds and see him photograph the
stars. The building is low one
story structure, and in 1t is big tube.
the old twenty tube, and on
one side we find, two ten-inch lenses
and a s.6-inch guiding telescope. 1t
is the Photographic telescope that has
taken pictures, as the layman would
say. of the, many wonderful things
In. the sky.
The Photographic telescope stands
on two brick piers. a large spoked
wheel, the kind that YOU used to see
on deep-water craft, is the means by
which the roof is slid back so that
clear view of the heavens may be
obtained A turn of the motor and
you are all ready to get in position
for the taking of the photograph. The
plates are in position and you think
minute, for we must flrst locate the
star or object to be caught" There
is no guesswork about ii. At last
we have sighted the object that we
want. and now we must depend upon
|, the clock to turn the tube SO as to
keep the object always in range. The
device that performs this Office for
us is known as the electric driving
clock. A small motor supplies the
power that turns rod on which is a
twenty-pound bronze fywheel. This
is accurately balanced and keyed TO
the shaft. the shaft turns gears and
plates. the latter are so constructed
as to make and break, so that there
will be just the interval needed, and
the upright brass rod. when the
clutch is thrown in. completes the
proper position
The device was made by Prof.
Peters. who was aided in the me-
chanical details and delicate adjust
ments required by J. Rheinbold of
the nautical repair shop.
**
THERE are only two or three
i places in the world where there
is what you would call first-class
seeing" and Washington is not in
cluded in the list, although the con-
ditions here are much better than
they are at the majority of places
Another point that may be of in
terest to many is the fact that you
can see stars in the daytime, pro-
| vided, of course. you have a good
telescope and you know where to look
| for them.
Before leaving the subject. OF the
Photographic telescope, and lest the
| reader is thinking of going out to-
morrow morning and buying such an
instrument. 1t is but fair to say that
the two lenses used would today cost
about $4,000. to say nothing of the
rest of the apparatus, or, II you de-
sire and know how, you can spend a
year in making. these lenses.
| 1t must not be-thouEht that Prof
Peters has been content to take pho
tographs only of bodiesfof the sky
! that everybody knows about. He has
been exploring the great blue dome
for some time, and some of the things
that he has discovered are:The Wash