d, another cloud of
vapour. The fall--for such it proved to be--was more beautiful than
the other, for, though the volume of water was not so great, it fell at
one leap, without a break, and at the same tremendous speed, a distance
of more than a thousand feet. The canon rang with the echoes, while
the spray flew in sheets against the smooth, glistening, sandstone
walls. Instead of coming from a river, as the first fall had, this
poured at once from the rocky lip, about two miles across, of a lake
that was eleven hundred feet above the surging mass in the vale below.

"It is a thousand pities," said Bearwarden, "that this cataract has got
so near its source; for, at the rate these streams must cut, this one
in a few hundred years, unless something is done to prevent it, will
have worn back to the lake, and then good-bye to the falls, which will
become a series of rapids. Perhaps the first effect will be merely to
reduce by a few feet the height of the falls, in which case they will
remain in practically the same place."

About the shores of this lake they saw rhinoceroses with long thick
wool, and herds of creatures that much resembled buffaloes.

"I do not see," said Bearwarden, "why the identical species should not
exist here that till recently, in a geological sense, inhabited the
earth. The climate and all other conditions are practically the same
on both planets, except a trifling difference in weight, to which
terrestrials would soon adapt themselves. We know by spectroscopic
analysis that hydrogen, iron, magnesium, and all our best-known
substances exist in the sun, and even the stars, while the earth
contains everything we have found in meteorites. Then why make an
exception of life, instead of supposing that at corresponding periods
of development the same living forms inhabit all? It would be assuming
the eternal sterilization of the functions of Nature to suppose that
our earth is the only body that can produce them."

"The world of organic life is so much more complex," replied Cortlandt,
"than that of the crystal, that it requires great continuity. So far
we certainly have seen no men, or anything like them, not even so much
as a monkey, though I suppose, according to your reasoning, Jupiter has
not advanced far enough to produce even that."

"Exactly," replied Bearwarden, "for it will require vast periods; and,
according to my belief, at least half the earth's time of habitability
had passed