Then, without any warning, it hunched itself up and drew a little farther back.

There was no longer any doubt.
It was a human being, lying on its stomach with its head turned to the sea.
Julian, who had entered upon his adventure with the supercilious incredulity of a staunch unbeliever invited to a spiritualist's seance, was conscious for a moment of an absolutely new sensation.

A person of acute psychological instincts, he found himself analysing that sensation almost as soon as it was conceived.
"There is no doubt," he confessed under his breath, "that I am afraid!" His heart was beating with unaccustomed vigour; he was conscious of an acute tingling in all his senses.

Then, still lying on his stomach, almost holding his breath, he saw the thin line of light from an electric torch steal out along the surface of the sea, obviously from the hand of his fellow watcher.

Almost at that same moment the undefined agitation which had assailed him passed.