er where
we'll pass her?"

"About Ludlow's Island," answered Sam, who was developing a good
knowledge of the lakes.

"Ludlow's Island," repeated the mate. "The channel there is quite
narrow. We'll have to pass quite close."

"Do you think he'll see you, Uncle Joe?"

"No--of course not. What does it matter? I'm not keeping out of his
way. I had certain reasons for not wanting that officer to take me to
court; that's why I leaped overboard that time."

"Oh," answered Sam, who had not heard the explanation given by Nat and
the policeman.

"So we'll pass his vessel quite close," murmured the mate, when his
nephew had left him. "That's my chance. If I can be left in charge of
the wheel I think I can make Nat Morton wish he had never interfered
with me. Let's see, we ought to get to Ludlow's Island to-morrow
night. I hope it's dark or foggy."

Meanwhile, all unconscious of the perils in store for him, Nat was,
that same day, guiding the vessel of which he was now officially the
assistant pilot toward Detroit.

"It's going to be a thick night," said Mr. Weatherby, as Nat relieved
him in the pilot-house, the evening of the day after the conversation
set down above between Sam Shaw and his uncle. "I think there will be
quite a fog before morning. Don't take any chances. If you're in
doubt call me, but I'd like you to try your hand at taking the ship
past Ludlow's Island. It's one of the worst places in the lake, and
when you've been through that, in a fog, you're almost entitled to a
pilot's license."

"I'll try it, Mr. Weatherby."

"That's the way to talk."

As the night came on the fog increased, until Nat decided he would
slow down to half speed. The bell and whistle were kept going at
regular intervals, and two men were stationed in the bow as lookouts.

It was close to midnight when Nat, who had decided to ask to be
relieved, for he was a little doubtful of his ability under such bad
conditions, saw through the haze another vessel approaching. He was in
the narrowest part of the channel.

"There isn't time to send word to Mr. Weatherby now," he thought.
"I'll wait until I pass that ship. Then I'll go below, for I'm getting
nervous here."

The two vessels were approaching nearer and nearer to each other. If
Nat had been aware that the ship he was about to pass was the one on
which was his enemy, the mate, doubtless he would have been more
nervous than he was.

"He seems to be crowding too close over thi