I found him squatting on his heels, with his thumb in his mouth and the other hand clasping a small object that, from his glance, seemed to have pleased him inordinately.

“I’ve found it, Miss Keate,” he said, achieving triumphant utterance in spite of the thumb. “Look! Could it have been this?”

It was a mercy I was so near the ground for my knees simply caved in under me. In his hand was a small hypodermic syringe. The nickel on it was rusted a little from the weather.

This syringe whizzing over my shoulder was exactly what I had seen. It was heavy enough to acquire considerable velocity and, as I peered through the shrubbery and trees to the porch, I knew that it would have fallen about here. The trouble was that it looked very much like the south wing’s missing syringe. Of course, all hypodermics are much alike, but I knew a certain way that it could be identified, for Maida had taken a cue from me and marked all her tools with a small scratched “D.”

“Let me see it,” I said.

Without a word he handed the thing to me. On the top of the little flat button was a rudely scratched “D,” rusty but still distinct.

“I see you recognize it,” said O’Leary, taking his thumb out of his mouth, and regarding it as thoughtfully as if he had not another object in the world. “It is Miss Day’s, is it not?”

I nodded.

“Everyone in the wing had access to it. The fact that it may have originally belonged to Maida doesn’t mean that she threw it out here.”

“No—no, of course not,” he said contemplatively. “Well—we found it, Miss Keate. Though I could wish that I had not run into it so forcibly.”