'Shooting stars,' that is to say, stones which fall to the earth, are
known to swarm in their wake, and are believed to be as plentiful in
space as fishes in the sea."

"The trash or leavings of creation," said I reflectively.

"And the raw material, for nothing is lost," rejoined Gazen. "Now, in
spite of all its diversity, there is a remarkable symmetry in the solar
system. The planets are all moving round the sun in one direction along
circular paths. As a rule each is nearly as far again from the sun as
the next within it. Thus, if we take Mercury as ¾ inch from the sun,
Venus is about 1¼ inches, the Earth 2¼, Mars 2, the planetoids 5¼,
Jupiter 9¾, Saturn 14, Uranus 36, and Neptune 60 inches. On the same
scale, by the way, Enckes' comet at Aphelion, its farthest distance from
the sun, would be about 12 feet; Donatis almost a mile; and Alpha
Centauri, a near star in the Milky Way, some ten miles.

"The stately march of the planets in their orbits becomes slower the
farther they are from the sun. The velocity of Mercury in its orbit is
thirty, that of Jupiter is eight, and that of Neptune is only three
miles a second. On the other hand, the inner planets, as a rule, take
some twenty-four hours, and the outer only ten hours to spin round their
axis. The inner planets are small in comparison with the outer. If we
represent the sun by a gourd, 20 inches in diameter, Mercury will seem a
bilberry (⅟₁₆ inch) Venus, a white currant, the Earth a black currant
(¼ inch), Mars a red currant (⅛ inch), the planetoids as fine seed,
Jupiter an orange or peach (2 inches), Saturn a nectarine or greengage
(1 inch), Uranus a red cherry (¾ inch), and Neptune a white cherry
(barely 1 inch in diameter). By putting the sun and planets in a row,
and drawing a contour of the whole, we obtain the figure of a dirk, a