Spirit of the age. [volume] (Woodstock, Vt.) 1845-1913, 1877-10-31
Mars.

the telescope with which he had dis
covered the moons of Jupiter, the
crescent form of Venus, and many
other wonders in the heavens, he was
altogether disappointed His tele-
scope was indeed too small to show
any features of interest in Mars,
though the planet Of war is much
nearer to us than Jupiter. Mars is
but a small world. The, diameter Of
the planet is about 4,400 miles, that
Of our earth being nearly 5000. Ju,
piter, though much farther away, has
his immense diameter of more than
10000 miles to make up, and much
more than make up, for the effect of
distance. With his noble system of
moons he appears remarkable object
even with small telescope, but Mars
shows fewer features Of interest even
with telescopes of considerable size.
1t was not, then, till very powerful
telescopes had been constructed that
astronomers learned what we ,now
know about Mars.
1t is found that his surface is divid-
ed into land and water, like the sur.
face of our own earth. But his seas
and oceans are not nearly so large
compared with his continents and
lands. You know that on our own
earth the water covers so much larger
a surface than the land that the great
continents are in reality islands. Eu.
rope, Asia and Africa together form
one great island North aud South
America another, not quite SO large ;
then come Australia, Greenland, Mad
agascar, and 50 forth all the lands
being islands, larger or smaller. On
the other hand, except the Caspian
Sea and the Sea of Aral, there arc no
large seas entirely land bound. In
the case of Mars very different state
Of things prevails, as you will see
from the three accompanying pictures
Nitherto unpublished), drawn by the
famous English observer, Dawes
Called the Eagle-eyed). The third
and best was drawn with n telescope
constructed by your famous optician,
Alvin Clark, of Cambridge, Massachu-
sets. The dark parts are the seas,
the light parts being land, or in some
cases cloud or snow. But in these
pictures most of the lighter portions
represent land; for they have been
seen often so shaped, whereas clouds,
of course, would change in shape.
The planet Mars, like our cartl'
turns on its axis. so that it has day
and night as We have. The length of
Its day is not very different from that
of our own day. Our earth turns once
on its axis in --- but before reading
on, try to complete this sentence for
yourself. Every one knows that the
earth's turning on its axis produces
day and night, and nine persons out
of ten, if asked how long the earth
takes in turning round her axis, will
answer, "a hours and if asked how
many times she turns OH her axis in i
year, will say 365 times; or if disposed
to be very exact, "about 3654 times" ."
But neither answer is correct. The
earth turns on her axis about 1861
times in each year, and each turning
occupies 23 hours Sc minutes and 4
seconds and tenth of second We,
taking the ordinary day as the time of
a turning or rotation, lose count OF
one rotation each year, 1t is necessary
to mention this, in order that when |
tell you how long the day of Mars is,
You may be able correctly to compare
it with our own day. Mars, then,
turns on bis axis in "a hours 81 min
utes 22 seconds and 7 tenth-parts OF q
second. So that Mars requires Al
minutes Is seconds and 6.tenths OF a
second longer to turn his small body
once round than our earth requires TO
turn round her much larger body
The common day OF Mars is, however,
only abo1t SO minutes longer than our
common day.
Mars has long year, taking no less
than 6s7 Of our days to complete his
circuit round the sun, so that his year
lasts only about one month and half
less than two of ours
Like the earth, Mars has seasons,
for his polar axis, like that of the
earth, is aslant, and at one part of his
year brings his northern regions more
fully into sunlight, at which time the
summer prevails there and winter in
his southern regions; when at the op.
posite part of his year his southern