he unused film go, and send the roll to be developed and printed;
and I picked up the camera--"

"Yes," said the Tracer softly.

"I picked it up and was starting toward the window where there remained
enough daylight to see by--"

The Tracer nodded gently.

"Then I saw _her_!" said Harren under his breath.

"Where?"

"There--standing by that window. You can see the window and curtain in
the photograph."

The Tracer gazed intently at the picture.

"She looked at me," said Harren, steadying his voice. "She was as real
as you are, and she stood there, smiling faintly, her dark, lovely eyes
meeting mine."

"Did you speak?"

"No."

"How long did she remain there?"

"I don't know--time seemed to stop--the world--everything grew still.
. . . Then, little by little, something began to stir under my stunned
senses--that germ of misgiving, that dreadful doubt of my own sanity.
. . . I scarcely knew what I was doing when I took the photograph;
besides, it had grown quite dark, and I could scarcely see her." He drew
himself erect with a nervous movement. "How on earth could I have
obtained that photograph of her in the darkness?" he demanded.

"N-rays," said the Tracer coolly. "It has been done in France."

"Yes, from living people, but--"

"What the N-ray is in living organisms, we must call, for lack of a
better term, the subaura in the phantom."

They bent over the photograph together. Presently the Tracer said: "She
is very, very beautiful?"

Harren's dry lips unclosed, but he uttered no sound.

"She is beautiful, is she not?" repeated the Tracer, turning to look at
the young man.

"Can you not see she is?" he asked impatiently.

"No," said the Tracer.

Harren stared at him.

"Captain Harren," continued the Tracer, "I can see nothing upon this bit
of paper that resembles in the remotest degree a human face or figure."

Harren turned white.

"Not that I doubt that _you_ can see it," pursued the Tracer calmly. "I
simply repeat that I see absolutely nothing on this paper except a part
of a curtain, a window pane, and--and--"

"What! for God's sake!" cried Harren hoarsely.

"I don't know yet. Wait; let me study it."

"Can you not see her face, her eyes? _Don't_ you see that exquisite slim
figure standing there by the curtain?" demanded Harren, laying his
shaking finger on the photograph. "Why, man, it is as clear, as clean
cut, as distinct as though the picture had been taken in sunlight! Do
yo