ent me a letter asking me to take
your place, and wear your dress, which I was to obtain by presenting
your note to the costumer. I did this, fully intending to carry out your
wishes."

"Then how was it that Fisher wore my costume?"

"I am coming to that. Just before leaving for the affair, who should
call here but the costumer, who informed me that a man had been to his
place, and had catechised him about me, explaining that he was a
detective hunting down a celebrated criminal. He showed the fellow your
note. Afterwards he regretted having done so, and came to notify me, as
he expressed it, 'so that I might not get into any trouble.' I saw at
once that this meant that Barnes would be at the festival, or, at any
rate, one of his men."

"You were right in that. He was there."

"Yes, but I was not sure of it till after the robbery, when all
unmasked. He wore one of the Forty Thieves dominos, and I failed to see
through the disguise. With the knowledge thus obtained, I determined to
have some amusement at the expense of your great detective, and decided
to wear one of the dominos instead of your dress. It was essential,
however, that some one should impersonate Ali Baba in order that the
tableaux might not be interrupted. Fisher was the only man I could ask
to assume the _role_. He acquiesced, and that is all there was to that.
I have not taken him up again, I assure you."

"Very good. That is satisfactory. You must pardon my questioning; but
after all, I did not understand, and had a right to do so. Tell me, were
you near when the robbery occurred? Did you see it done?"

"I must have been near, but I did not see it. I was awaiting to kiss the
hand of the Scheherezade when Mr. Barnes suddenly cried out that a
robbery had been committed, and ordered masks off. I slipped out of my
domino, and went to him as soon as the lights were on."

"You might have suggested to him to search everybody, as he did on the
train."

"By George! that is just what I did, but he declined. I guess that train
experience made him dubious as to the value of that sort of thing."

At this both men laughed heartily, as though enjoying the discomfiture
of the detective.

"It seems," said Mr. Mitchel, "that Barnes suspected that the ruby was
to be stolen, and informed Mr. Rawlston early in the evening that there
would be thieves in the audience."

"Did he, indeed? Too bad that, with all his shrewdness, he was not able
to catch the thief, o