n agitation of the
waters, which swelled upward at the foot of the rocks.

"It is like the swell from a vessel," said Wells.

"Yes," said I, instinctively lowering my voice. "What has caused it?
The wind has completely died out. Does it come from something on the
surface of the lake?"

"Or from something underneath," said Wells, bending forward, the
better to determine.

The commotion certainly seemed as if caused by some boat, whether
from beneath the water, or approaching the creek from outside upon
the lake.

Silent, motionless, we strained eyes and ears to pierce the profound
obscurity. The faint noise of the waves of the lake lapping on the
shore beyond the creek, came to us distinctly through the night. John
Hart and Nab Walker drew a little aside upon a higher ridge of rocks.
As for me, I leaned close to the water to watch the agitation. It did
not lessen. On the contrary it became momentarily more evident, and
I began to distinguish a sort of regular throbbing, like that
produced by a screw in motion.

"There is no doubt," declared Wells, leaning close to me, "there is a
boat coming toward us."

"There certainly is," responded I, "unless they have whales or sharks
in Lake Erie."

"No, it is a boat," repeated Wells. "Is she headed toward the mouth
of the creek, or is she going further up it?"

"This is just where you saw the boat twice before?"

"Yes, just here."

"Then if this is the same one, and it can be no other, she will
probably return to the same spot."

"There!" whispered Wells, extending his hand toward the entrance of
the creek.

Our companions rejoined us, and all four, crouching low upon the
bank, peered in the direction he pointed.

We vaguely distinguished a black mass moving through the darkness. It
advanced very slowly and was still outside the creek, upon the lake,
perhaps a cable's length to the northeast. We could scarcely hear
even now the faint throbbing of its engines. Perhaps they had stopped
and the boat was only gliding forward under their previous impulse.

It seemed, then, that this was indeed the submarine which Wells had
watched, and it was returning to pass this night, like the last,
within the shelter of the creek.

Why had it left the anchorage, if only to return? Had it suffered
some new disaster, which again impaired its power? Or had it been
before compelled to leave, with its repairs still unfinished? What
cause constrained it to return here? Was there s