He stood staring at me, and I could see the horror of the situation
dawning in his face.

"I can't tell you where I went, Aunt Ray," he said, after a moment.
"As to why, you will learn that soon enough. But Gertrude knows that
Jack and I left the house before this thing--this horrible
murder--occurred."

"Mr. Jamieson does not believe me," Gertrude said drearily. "Halsey, if
the worst comes, if they should arrest you, you must--tell."

"I shall tell nothing," he said with a new sternness in his voice.
"Aunt Ray, it was necessary for Jack and me to leave that night. I can
not tell you why--just yet. As to where we went, if I have to depend
on that as an alibi, I shall not tell. The whole thing is an
absurdity, a trumped-up charge that can not possibly be serious."

"Has Mr. Bailey gone back to the city," I demanded, "or to the club?"

"Neither," defiantly; "at the present moment I do not know where he is."

"Halsey," I asked gravely, leaning forward, "have you the slightest
suspicion who killed Arnold Armstrong? The police think he was
admitted from within, and that he was shot down from above, by someone
on the circular staircase."

"I know nothing of it," he maintained; but I fancied I caught a sudden
glance at Gertrude, a flash of something that died as it came.

As quietly, as calmly as I could, I went over the whole story, from the
night Liddy and I had been alone up to the strange experience of Rosie
and her pursuer. The basket still stood on the table, a mute witness
to this last mystifying occurrence.

"There is something else," I said hesitatingly, at the last. "Halsey, I
have never told this even to Gertrude, but the morning after the crime,
I found, in a tulip bed, a revolver. It--it was yours, Halsey."

For an appreciable moment Halsey stared at me. Then he turned to
Gertrude.

"My revolver, Trude!" he exclaimed. "Why, Jack took my revolver with
him, didn't he?"

"Oh, for Heaven's sake don't say that," I implored. "The detective
thinks possibly Jack Bailey came back, and--and the thing happened
then."

"He didn't come back," Halsey said sternly. "Gertrude, when you
brought down a revolver that night for Jack to take with him, what one
did you bring? Mine?"

Gertrude was defiant now.

"No. Yours was loaded, and I was afraid of what Jack might do. I gave
him one I have had for a year or two. It was empty."

Halsey threw up both hands despairingly.

"If that isn't like a girl