"It's in my bedroom; you don't mind if I go on working out this cipher while you're telephoning?"

"Not in the least," said the Tracer blandly. He walked into the Captain's bedroom, closing the door behind him; then he stepped over to the telephone, unhooked the receiver, and called up his own headquarters.

"h.e.l.lo. This is Mr. Keen. I want to speak to Miss Borrow."

In a few moments Miss Borrow answered: "I am here, Mr. Keen."

"Good. Look up the name Inwood. Try New York first--Edith Inwood is the name. Look sharp, please; I am holding the wire."

He held it for ten full minutes; then Miss Borrow's low voice called him over the wire.

"Go ahead," said the Tracer quietly.

"There is only one Edith Inwood in New York, Mr. Keen--Miss Edith Inwood, graduate of Barnard, 1902--left an orphan 1903 and obliged to support herself--became an a.s.sistant to Professor Boggs of the Museum of Inscriptions. Is considered an authority upon Arabian cryptograms. Has written a monograph on the Herati symbol--a short treatise on the Swastika. She is twenty-four years of age. Do you require further details?"

"No," said the Tracer; "please ring off."

Then he called up General Information. "I want the Museum of Inscriptions. Get me their number, please." After a moment: "Is this the Museum of Inscriptions?"

"Is Professor Boggs there?"

"Is this Professor Boggs?"

"Could you find time to decipher an inscription for me at once?"

"Of course I know you are extremely busy, but have you no a.s.sistant who could do it?"

"What did you say her name is? Miss Inwood?"

"Oh! And will the young lady translate the inscription at once if I send a copy of it to her by messenger?"

"Thank you very much, Professor. I will send a messenger to Miss Inwood with a copy of the inscription. Good-by."

He hung up the receiver, turned thoughtfully, opened the door again, and walked into the sunlit living room.

"Look here!" cried the Captain in a high state of excitement. "I've got a lot of numbers out of it already."

"Wonderful!" murmured the Tracer, looking over the young man's broad shoulders at a sheet of paper bearing these numbers:

9--14--5--22--5--18--19--1--23--25--15--21--2--21--20--15--14--3--5-- 9--12--15--22--5--25--15--21--5--4--9--20--8--9--14--23--15--15--4.

"Marvelous!" repeated the Tracer, smiling. "Now what _do_ you suppose those numbers can stand for?"

"Letters!" announced the Captain triumphantly. "Take the number nine, for example. The ninth letter in the alphabet is I! Mr. Keen, suppose we try writing down the letters according to that system!"

"Suppose we do," agreed the Tracer gravely.

So, counting under his breath, the young man set down the letters in the following order, not attempting to group them into words:

INEVERSAWYOUBUTONCEILOVEYOUEDITHINWOOD.

Then he leaned back, excited, triumphant.

"There you are!" he said; "only, of course, it makes no sense." He examined it in silence, and gradually a hopeless expression effaced the animation. "How the deuce am I going to separate that ma.s.s of letters into words?" he muttered.

"This way," said the Tracer, smilingly taking the pencil from his fingers, and he wrote: I--NEVER--SAW--YOU--BUT--ONCE. I--LOVE--YOU.

EDITH INWOOD.

Then he laid the pencil on the table and walked to the window.

Once or twice he fancied that he heard incoherent sounds behind him.

And after a while he turned, retracing his steps leisurely. Captain Harren, extremely pink, stood tugging at his short mustache and studying the papers on the desk.

"Well?" inquired the Tracer, amused.

The young man pointed to the translation with unsteady finger. "W-what on earth does that mean?" he demanded shakily. "Who is Edith Inwood?

W-what on earth does that cryptogram mean on the window pane in the photograph? How did it come there? It isn't on my window pane, you see!"

The Tracer said quietly: "That is not a photograph of your window."

"What!"

"No, Captain. Here! Look at it closely through this gla.s.s. There are sixteen small panes in that sash; now count the panes in your window--eight! Besides, look at that curtain. It is made of some figured stuff like chintz. Now, look at your own curtain yonder! It is of plain velour."

"But--but I took that photograph! She stood there--there by that very window!"

The Tracer leaned over the photograph, examining it through the gla.s.s.

And, studying it, he said: "Do you still see _her_ in this photograph, Captain Harren?"

"Certainly. Can you not see her?"

"No," murmured the Tracer, "but I see the window which she really stood by when her phantom came here seeking you. And that is sufficient. Come, Captain Harren, we are going out together."

The Captain looked at him earnestly; something in Mr. Keen's eyes seemed to fascinate him.