well, smiling; "what else can it be?"

"It _is_ a knife," faintly interposed Arnold.

"Did you see the blade?" Entrefort asked him, quickly.

"I did--for a moment."

Entrefort shot a quick look at Dr. Rowell and whispered, "Then it is
_not_ suicide." Dr. Rowell looked puzzled and said nothing.

"I must disagree with you, gentlemen," quietly remarked Entrefort;
"this is not a knife." He examined the handle very narrowly. Not only
was the blade entirely concealed from view within Arnold's body, but
the blow had been so strongly delivered that the skin was depressed by
the guard. "The fact that it is not a knife presents a very curious
series of facts and contingencies," pursued Entrefort, with amazing
coolness, "some of which are, so far as I am informed, entirely novel
in the history of surgery."

A quizzical expression, faintly amused and manifestly interested, was
upon Dr. Rowell's face. "What is the weapon, doctor?" he asked.

"A stiletto."

Arnold started. Dr. Rowell appeared confused. "I must confess," he
said, "my ignorance of the differences among these penetrating weapons,
whether dirks, daggers, stilettos, poniards, or bowie-knives."

"With the exception of the stiletto," explained Entrefort, "all the
weapons you mention have one or two edges, so that in penetrating they
cut their way. A stiletto is round, is ordinarily about half an inch or
less in diameter at the guard, and tapers to a sharp point. It
penetrates solely by pushing the tissues aside in all directions. You
will understand the importance of that point."

Dr. Rowell nodded, more deeply interested than ever.

"How do you know it is a stiletto, Dr. Entrefort?" I asked.

"The cutting of these stones is the work of Italian lapidaries," he
said, "and they were set in Genoa. Notice, too, the guard. It is much
broader and shorter than the guard of an edged weapon; in fact, it is
nearly round. This weapon is about four hundred years old, and would be
cheap at twenty thousand florins. Observe, also, the darkening color of
your friend's breast in the immediate vicinity of the guard; this
indicates that the tissues have been bruised by the crowding of the
'blade,' if I may use the term."

"What has all this to do with me?" asked the dying man.

"Perhaps a great deal, perhaps nothing. It brings a single ray of hope
into your desperate condition."

Arnold's eyes sparkled and he caught his breath. A tremor passed all
through him, and I felt it