The midland journal. (Rising Sun, Md.) 1885-1947, 1891-08-21
TALKING WITH STARS.
RoFESsoR DAvlDsoNs VIEWS OF
lNTERPLAN- -TARY SIGNALS.


rhe suggested Use OF Huge Triangle
in the Desert of .. hara- -Improbability
That the Attenl Is VIII BE Successful.
When Professor George Davidson of
She Davidson Observatory and the Coast
md Geodetic Survey was shown the Paris
ablegram saying that an old lady had
iust died at Spa, leaving 100.000f. as a
prize to the Astronomer, French or
foreign, who within 10 years shall be
able to communicate with any planet or
star, reread it through slowly once, then
he read it twice more rapidly. Finally
he picked it up. held it at proper dis
tance from his eyes, and squinted at it
Just as he would squint at Mercury
through his telescope if he wanted to find
the big tortoise shaped spot on its
northern hemisphere.
"An old lady-an old lady" the veteran
astronomer finally exclaimed. "Now,
isn't that pretty way to treat such a
piece of philan.hi opy as that?" An old
lady, indeed! Now, why under the sun
do you suppose they keep back her name
am inclined to be ieve that some good
looking young m~..-one of these smooth
talsers-has been .r,;utting close to her and
talking a lot Of astronomy into her ear.
Professor Davidson picked up a blue
pencil and drew Oh white sheet of paper
right angled triangle.
@This that / have drawn, he said, "is
the old triangle Of Pythagoras. That
triangle has right angle, and the square
built upon the side opposite the right
angle is equal to tie sum of the squares
built upon the otter two sides. The
proposition is said to be the fundamental
one of geometry. 1t has been proposed
to draw such Fl .:ure as that in the
Desert of Sahara, or some other great
plain, the lines, of c ,urse, to be hundreds
of miles long, and made so they would
be distinct on the de ert sand.
aThese are the f.ppositions that go
along with the la. 1t is supposed
that there are people on some of the
planets, at least on Mars. 1t is supposed
that the people on the planet are civilized
and capA.ue Of To- king through tele-
scopes, and it is concluded that If this is
SO, they must know the Pythagorean
proposition.
$50, if the people on Mars look through
their telescopes at the earth they will be
sure to see that enormous figure on the
desert, and SEEN 1t they will realize
that the earth is Inhabited by men of
knowledge, and that the drawing is a
signal. Then, of course, they will set to
work to answer it by building just such
figure on Mas. That will be talking
from star to star.
"But all this is bosh and nonsense to
me, and dare say it was bosh and non-
sense to the nal who wheedled this
Frenchwoman iLto setting aside her
100, 600 francs. But whoever he was, he
knew on which slD.e his bread was but
tered, and knew that such a trust, for
whatever purpose, would bear interest.
"Buteven surprising that the Desert of
Sahara is one great plain and that it is
large enough for the purpose, and even
supposing that it was possible to make
such an enormous figure, am in doubt
whether the people on Mars, with such
telescopes as we use, would be able to
see it.
"At certain times Mars is but $4,000
900 miles from the earth, but it gets fur
ther and further away, until the distance
is 81 800, 900 miles. That is a good way
off to see triangles. But if Mars is in
habited am inclined to believe that the
inhabitants are not fools. Ii they saw
triangle shaped object on the face of the
earth they would not jump to the chi.
merical conclusion that there were idiots
enough down here to build such an af-
fair.
@The truth is we do not know whether
any of the planets hesides the earth arc
inhabited. We th.1k we know that il
might be possible Tor men to live OF
Mercury. ThesitLario and condition Of
things on the other planets are altogether
lifferent from those on the earth. So,
when we talk about the inhabitants of
the planets we enter the realms of sur
mise, and Jules Verne has better chance
than the scientist.
"The four planets nearest the sun are
Mercury, Venus, the earth, and Mars.
Mercury is only 35, 500 900 miles from the
sun, which isn't We. y far when you take
the heat into consideration. Conse-
quently we believe it is good many
times hotter than Arizona on Mercury.
There are other disadvantages, such as a
lack Of space, enol ..lous mountains, and
no certainty of atmosphere. Mercury is
only 5000 miles in diameter, yet there
are mountains on its surface over 10
miles high.
venus is 66, 1874. 900 miles from the
sun, ann is plenty hot enough, although
nearly twice as far as Mercury from the
great heater. Then there is some ques-
ton about the atmosphere as yet, and the
year is only 224 days long.
"The earth comes next, being 81 ,430,-
600 miles from the sun. After this planet
is Mars, 1875, ,311 900 miles from the lumi-
nary.
@All astronomers admit that If people
like those on the earth live on any of the
other planets Mars is probably the one.
The reason why is easy to tell. Although
Mars is further from the sun than the
earth his orbit is so eccentric that
at certain times he is only 1875, ,319,.
600 miles away, consequently the tenn.
peraturss are, likely, merely little
more moderate than those on the earth.
Then, too, the dinnal motion of the two
planets is about the same, SO that from
one years end to another the distance
from the earth to Mars varies only from
81, 800. 900 miles to 81 SOC. 600 miles. Mars
has its seasons and its polar ice, just like
the earth.