ing of the stream we ascended before
reaching this."

"We must remember," replied Cortlandt, "that many of the conditions are
different here from those that exist on earth. We know that some of
the streams are warm, and even hot, and that the temperature of
Deepwaters Bay, and doubtless that of the ocean also, is considerably
higher than ours. This would facilitate evaporation. The density of
the atmosphere and the tremendous winds, of which I suspect we may see
more later, must also help the sun very much in its work of raising
vapour. But the most potent factor is undoubtedly the vast size of the
basin that these rivers drain."

"The great speed at which the atmospheric currents move," said
Bearwarden, "coupled with the comparative lowness of the mountain
chains and the slight obstruction they offer to their passage, must
distribute the rain very thoroughly, notwithstanding the great unbroken
area of the continents. There can be no such state of things here as
exists in the western part of South America, where the Andes are so
high that any east-bound clouds, in crossing them, are shoved up so far
into a cold region that all moisture they may have brought from the
Pacific is condensed into rain, with which parts of the western slope
are deluged, while clouds from the Atlantic have come so far they have
already dispersed their moisture, in consequence of which the region
just east of the Andes gets little if any rain. It is bad for a
continent to have its high mountains near the ocean from which it
should get its rain, and good for it to have them set well back."

"I should not be surprised," said Cortlandt, "if we saw another
waterfall to-morrow, though not in the shape of rain. In the hour
before we stopped we began to see rapids and protruding rocks. That
means that we are coming to a part of the channel that is comparatively
new, since the older parts have had time to wear smooth. I take it,
then, that we are near the foot of a retreating cascade, which we may
hope soon to see. That is exactly the order in which we found smooth
water and rapids in river No. 1, which we have named the Harlem."

After this, not being tired, they used the remaining dark hours for
recording their recent adventures.

CHAPTER XII.

HILLS AND VALLEYS.

With the first light they resumed their journey, and an hour after
setting out they sighted, as Cortlandt had predicte