ons I went through the motion and came to the
conclusion that the marks were on the wrong side. Then I tried with my
left hand and accounted for it. The blue pencil made me suspicious. I
have no knowledge of a yacht-hand's duties, but surely sharpening blue
pencils is not one of them. Then the knife had also been carried in
the same pocket as a piece of white chalk. The only sort of person I
could think of who would carry a piece of chalk loose in his pocket
and use a blue pencil continuously was a schoolmaster. So I stated
definitely--there's nothing like bluff--that the knife belonged to the
left-handed man, who quite obviously had red hair, who appeared to
wear the insignia of the married state, and who--again according to
the law of averages--had at least one child. I naturally slumped the
schoolmaster idea in with it, and there you have the whole thing in a
nutshell. But it was Garnesk who set me looking for left-handed clues,
and if I hadn't been looking for it, it would never have entered my
head."

"But look here," I suggested, "some people sharpen pencils by pointing
the pencil to them. Wouldn't that produce the same effect?"

"Yes," he admitted, "I thought of that. But the marks would have been
very much fainter, because there would have been much less pressure. I
put that idea aside."

"Good!" I exclaimed. "I should much prefer to swallow your theory
whole, Dennis, but it struck me that might be a possible source of
error, which, of course, might have led us on to a false trail. And,
I say, those questions you asked about the time he stayed in port and
the hotel. Were those all bluff? Or had you some sort of idea at the
back of them?"

"I had a very definite idea at the back of them," Dennis replied. "I
thought perhaps the white chalk which was deposited in the blade-pocket,
and was even noticeable on the handle, might be due to billiard chalk.
But, of course, I didn't mention billiards, because it would have given
my line of reasoning away. I thought it was better to spring it on them
with a bump."

"Which you certainly did," I laughed. "As a matter of fact, I thought
you were simply having a game with us all. But now that you've told me
the details, Den, do you remember what happened when you did spring it
on them?"

"Well, of course I do," he replied. "But even so, I hardly know what
to make of it. I should like to feel confidently that Fuller is the
man we are after. But we must remember that both