a tiny drop of apparently fresh blood on it. Greene came over and looked
closely at it for some minutes. Then he sat back in his chair, looking
curiously at his friend's face.

"You've scratched yourself without knowing it," he said presently.

"There's no sign of a bruise. It must be something else that made the
arm ache."

Marriott sat very still, staring silently at his arm as though the
solution of the whole mystery lay there actually written upon the skin.

"What's the matter? I see nothing very strange about a scratch," said
Greene, in an unconvincing sort of voice. "It was your cuff links
probably. Last night in your excitement--"

But Marriott, white to the very lips, was trying to speak. The sweat
stood in great beads on his forehead. At last he leaned forward close to
his friend's face.

"Look," he said, in a low voice that shook a little. "Do you see that
red mark? I mean _underneath_ what you call the scratch?"

Greene admitted he saw something or other, and Marriott wiped the place
clean with his handkerchief and told him to look again more closely.

"Yes, I see," returned the other, lifting his head after a moment's
careful inspection. "It looks like an old scar."

"It _is_ an old scar," whispered Marriott, his lips trembling. "_Now_ it