ger longer in the lap of spring; summer
would be one hundred and eighty-one days long; but as the seas are
more intermingled with the land, and the divisions of land have less
of continental magnitude, it may be conjectured that Mars might be a
comfortable place of residence to beings like men. Perhaps the
greatest surprise to the earthly visitor would be to find himself
weighing only four-tenths as much as usual, able to leap twice as
high, and lift considerable bowlders.

_Satellites of Mars._

The night of August 11th, 1877, is famous in modern astronomy.
Mars has been a special object of study in all ages; but on that
evening Professor Hall, of Washington, discovered a satellite of
Mars. On the 16th it was seen again, and its orbital motion followed.
On the following night it was hidden behind the body of the planet
when the observation began, but at the calculated time--at four
o'clock in the morning--it emerged, and established its character as
a true moon, and not a fixed star or asteroid. Blessings, however,
never come singly, for another object soon emerged which proved
to be an inner satellite. This is extraordinarily near [Page 162]
the planet--only four thousand miles from the surface--and its
revolution is exceedingly rapid. The shortest period hitherto known
is that of the inner satellite of Saturn, 22h. 37m. The inner
satellite of Mars makes its revolution in 7h. 39m.--a rapidity so
much surpassing the axial revolution of the planet itself, that it
rises in the west and sets in the east, showing all phases of our
moon in one night. The outer satellite is 12,579 miles from Mars,
and makes its revolution in 30h. 18m. Its diameter is six and a
quarter miles; that of the inner one is seven and a half miles. This
can be estimated only by the amount of light given.

ASTEROIDS.

ALREADY DISCOVERED (1879), 192. DISTANCES FROM THE SUN, FROM 200,000,000
TO 315,000,000 MILES. DIAMETERS, FROM 20 TO 400 MILES. MASS OF ALL,
LESS THAN ONE-QUARTER OF THE EARTH.

The sense of infinite variety among the countless number of celestial
orbs has been growing rapidly upon us for half a century, and doubtless
will grow much more in half a century to come. Just as we paused
in the consideration of planets to consider meteors and comets,
at first thought so different, so must we now pause to consider a
ring of bodies, some of which are as small in comparison to Jupiter,
the next planet, as aerolites are compared to the ea