d come aboard at the last moment--a fussy graybeard who
kept the big ship waiting while he haggled with his boatman over half a
lira. But at length we were off, the tug was shed, the lighthouse
passed, and Raffles and I leaned together over the rail, watching our
shadows on the pale green, liquid, veined marble that again washed the
vessel's side.

Von Heumann was having his innings once more; it was part of the design
that he should remain in all day, and so postpone the inevitable hour;
and, though the lady looked bored, and was for ever glancing in our
direction, he seemed only too willing to avail himself of his
opportunities. But Raffles was moody and ill-at-ease. He had not the
air of a successful man. I could but opine that the impending parting
at Naples sat heavily on his spirit.

He would neither talk to me, nor would he let me go.

"Stop where you are, Bunny. I've things to tell you. Can you swim?"

"A bit."

"Ten miles?"

"Ten?" I burst out laughing. "Not one! Why do you ask?"

"We shall be within a ten miles' swim of the shore most of the day."

"What on earth are you driving at, Raffles?"

"Nothing; only I shall swim for it if the worst comes to the worst. I
suppose you can't swim under water at all?"

I did not answer his question. I scarcely heard it: cold beads were
bursting through my skin.

"Why should the worst come to the worst?" I whispered. "We aren't
found out, are we?"

"No."

"Then why speak as though we were?"

"We may be; an old enemy of ours is on board."

"An old enemy?"

"Mackenzie."

"Never!"

"The man with the beard who came aboard last."

"Are you sure?"

"Sure! I was only sorry to see you didn't recognize him too."

I took my handkerchief to my face; now that I thought of it, there had
been something familiar in the old man's gait, as well as something
rather youthful for his apparent years; his very beard seemed
unconvincing, now that I recalled it in the light of this horrible
revelation. I looked up and down the deck, but the old man was nowhere
to be seen.

"That's the worst of it," said Raffles. "I saw him go into the
captain's cabin twenty minutes ago."

"But what can have brought him?" I cried miserably. "Can it be a
coincidence--is it somebody else he's after?"

Raffles shook his head.

"Hardly this time."

"Then you think he's after you?"

"I've been afraid of it for some weeks."

"Yet there you stand!"

"What am I to do?