ck you wouldn't
have heard that infernal machine bumping against the hull."

"Infernal?" echoed Eph Somers, rubbing his eyes. "Say, have I been
missing a whole lot by being asleep?"

The other three told him quickly all they knew of what had happened.

Within five minutes the cutter came back, bringing two more marines
and a young second lieutenant of that corps.

"Lieutenant Commander Kimball's compliments, sir," reported the second
lieutenant. "He will put in an appearance as soon as that cylinder has
been investigated. He has sent me with instructions to see what had best
be done."

"I don't believe there's much doubt as to what had best be done,"
replied Captain Jack, quickly. "Williamson reports having cut a wire
that was attached to that cylinder. I think we can find that wire again,
and, if we do, we can easily follow it to its other end."

"By jove, that's good enough," muttered the lieutenant.

"Williamson is already wet," proposed Jack. "He can dive again, and see
whether he can pick up that wire. If he needs any help, I'll go
overboard with him."

"Wait until I see what I can do," proposed the machinist.

This time he dived over the port side of the craft. Three or four times
he came up for air, next going, below again. At last, however,
Williamson came up, calling:

"I have a part of the wire in my hands."

Lieutenant Foster ordered his marines into the cutter, inviting Jack
and Hal also to go with him. They rowed out alongside of Williamson,
picking up the machinist and his wire.

"We'd better put your man back on the boat, hadn't we, Mr. Benson?"
inquired the marine lieutenant.

"I'm not such weak stuff as that, sir," almost grumbled the machinist.
"I can stand a few minutes more in wet clothes, and I want to go along to
see where this wire leads."

"Good enough," nodded Lieutenant Foster, he gave the order to row along
slowly, while two marines in the bow of the cutter slowly gathered
in the wire, at the same time signaling back the direction in which it
lay.

Only a few minutes were needed thus to follow the trail straight to the
clump of bushes on shore.

"Nobody leave the boat until we have a lantern ready," directed
Lieutenant Foster. "We don't want to tramp out the trail of the rascals
who laid that mine."

The marine lieutenant himself was the first to step ashore, and Jack
Benson was with him.

"Here are the footprints of the rascals," announced Foster, as the two