We were already rather close in; but I ordered the U-33's prow
turned inshore and we crept slowly along, constantly dipping up
the water and tasting it to assure ourselves that we didn't get
outside the fresh-water current. There was a very light off-shore
wind and scarcely any breakers, so that the approach to the shore
was continued without finding bottom; yet though we were already
quite close, we saw no indication of any indention in the coast
from which even a tiny brooklet might issue, and certainly no
mouth of a large river such as this must necessarily be to freshen
the ocean even two hundred yards from shore. The tide was running
out, and this, together with the strong flow of the freshwater
current, would have prevented our going against the cliffs even
had we not been under power; as it was we had to buck the combined
forces in order to hold our position at all. We came up to within
twenty-five feet of the sheer wall, which loomed high above us.
There was no break in its forbidding face. As we watched the face
of the waters and searched the cliff's high face, Olson suggested
that the fresh water might come from a submarine geyser. This, he
said, would account for its heat; but even as he spoke a bush,
covered thickly with leaves and flowers, bubbled to the surface
and floated off astern.

"Flowering shrubs don't thrive in the subterranean caverns from
which geysers spring," suggested Bradley.

Olson shook his head. "It beats me," he said.

"I've got it!" I exclaimed suddenly. "Look there!" And I pointed
at the base of the cliff ahead of us, which the receding tide was