And again I thought of Gertrude’s sprained ankle.  Was it the right or the left?

CHAPTER VIII

THE OTHER HALF OF THE LINE

“Miss Innes,” the detective began, “what is your opinion of the figure you saw on the east veranda the night you and your maid were in the house alone?”

“It was a woman,” I said positively.

“And yet your maid affirms with equal positiveness that it was a man.”

“Nonsense,” I broke in.  “Liddy had her eyes shut—­she always shuts them when she’s frightened.”

“And you never thought then that the intruder who came later that night might be a woman—­the woman, in fact, whom you saw on the veranda?”

“I had reasons for thinking it was a man,” I said remembering the pearl cuff-link.

“Now we are getting down to business.  What were your reasons for thinking that?”

I hesitated.

“If you have any reason for believing that your midnight guest was Mr. Armstrong, other than his visit here the next night, you ought to tell me, Miss Innes.  We can take nothing for granted.  If, for instance, the intruder who dropped the bar and scratched the staircase—­you see, I know about that—­if this visitor was a woman, why should not the same woman have come back the following night, met Mr. Armstrong on the circular staircase, and in alarm shot him?”

“It was a man,” I reiterated.  And then, because I could think of no other reason for my statement, I told him about the pearl cuff-link.  He was intensely interested.

“Will you give me the link,” he said, when I finished, “or, at least, let me see it?  I consider it a most important clue.”

“Won’t the description do?”

“Not as well as the original.”

“Well, I’m very sorry,” I said, as calmly as I could, “I—­the thing is lost.  It—­it must have fallen out of a box on my dressing-table.”

Whatever he thought of my explanation, and I knew he doubted it, he made no sign.  He asked me to describe the link accurately, and I did so, while he glanced at a list he took from his pocket.

“One set monogram cuff-links,” he read, “one set plain pearl links, one set cuff-links, woman’s head set with diamonds and emeralds.  There is no mention of such a link as you describe, and yet, if your theory is right, Mr. Armstrong must have taken back in his cuffs one complete cuff-link, and a half, perhaps, of the other.”

The idea was new to me.  If it had not been the murdered man who had entered the house that night, who had it been?

“There are a number of strange things connected with this case,” the detective went on.  “Miss Gertrude Innes testified that she heard some one fumbling with the lock, that the door opened, and that almost immediately the shot was fired.  Now, Miss Innes, here is the strange part of that.  Mr. Armstrong had no key with him.  There was no key in the lock, or on the floor.  In other words, the evidence points absolutely to this:  Mr. Armstrong was admitted to the house from within.”