red line. There was
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
all comes back to me."

"All what?" Greene fidgeted on his chair. He tried to laugh, but without
success. His friend seemed bordering on collapse.

"Hush! Be quiet, and--I'll tell you," he said. "_Field made that scar._"

For a whole minute the two men looked each other full in the face
without speaking.

"Field made that scar!" repeated Marriott at length in a louder voice.

"Field! You mean--last night?"

"No, not last night. Years ago--at school, with his knife. And I made a
scar in his arm with mine." Marriott was talking rapidly now.

"We exchanged drops of blood in each other's cuts. He put a drop into my
arm and I put one into his--"

"In the name of heaven, what for?"

"It was a boys' compact. We made a sacred pledge, a bargain. I remember
it all perfectly now. We had been reading some dreadful book and we
swore to appear to one another--I mean, whoever died first swore to show
himself to the other. And we sealed the compact with each other's blood.
I remember it all so well--the hot summer afternoon in the playground,
seven years ago--and one of the masters caught us and confiscated the
knives--and I have never thought of i