will speak of that again.
Where can I put you down? Mr. Sydenham I shall carry off to my house; I
want to have a talk with him."

But Indiman declined to re-enter the coach, pleading some further
business down-town, and, of course, I remained with him. The carriage
was about to drive off when Indiman put up his hand.

"How stupid of me!" he exclaimed. "I had almost forgotten." He took
from the pocket of his overcoat a rather bulky package and handed it to
young Mr. Sydenham. "They'll explain themselves," he said, smiling. The
coach rolled away.

"The missing letters from V. S.," said Indiman, in answer to my look of
inquiry. "An average of two a day, and all addressed to him at the
Utinam. Well, what was the poor girl to do? The young fool had changed
his lodgings and obliterated every possible trace of his whereabouts.
All Miss Sandford had to go on was the bare intimation that he could be
addressed at the Utinam Club. She might as well have posted her
communications in the North River."

"I don't follow you."

"Two days ago I put a dummy letter addressed to Sydenham in his private
lock-box at the Utinam. I had promised, you know, to send him on his
mail if he would keep away from the club, and accordingly I had the key
of the letter-box in my possession. Ten minutes later I went again to
the box and it was empty--that is, you could see distinctly from one
end of the box to the other, and it was absolutely bare."

"A duplicate key, of course."

"Not at all. It is only a stupid person who descends to crime--except
as a last resort."

"Well, then?"

"Did you ever attend any of the exhibitions at the old Egyptian Hall?
One of the favorite illusions was the trick cabinet in which the
performer seated himself in full view of the spectators. The doors
would be closed for an instant, and then, when reopened, the man had
disappeared. The full interior of the cabinet was plainly visible; it
stood on legs, which precluded the idea of a trap-door, and it was
incontestably shown that egress from the back, top, or sides was
impossible."

"Yet the performer was gone?"

"I said that the cabinet appeared to be empty--quite another thing."

"Go on."

"It was a simple arrangement of plate-glass mirrors fitting closely at
the sides and backed by the distinctive pattern of wall-paper with
which the rest of the cabinet was covered. Immediately that the doors
were closed, the performer drew these false sides outward, so th