During the rest of the morning Craig was at work again in the laboratory.  He was busily engaged in testing something through his powerful microscopes and had a large number of curious microphotographs spread out on the table.  As I watched him, apparently there was nothing but the blood-stained gauze bandage which had been fastened to the face of the strange, light-haired woman, and on the stains on this bandage he was concentrating his attention.  I could not imagine what he expected to discover from it.

I waited for Kennedy to speak, but he was too busy more than to notice that I had come in.  I fell to thinking of that woman.  And the more I thought of the fair face, the more I was puzzled by it.  I felt somehow or other that I had seen it somewhere before, yet could not place it.

A second time I examined the unpublished photograph of Betty Blackwell as well as the pictures that had been published.  The only conclusion that I could come to was that it could not be she, for although she was light-haired and of fair complexion, the face as I remembered it was that of a mature woman who was much larger than the slight Betty.  I was sure of that.

Every time I reasoned it out I came to the same contradictory conclusion that I had seen her, and I hadn’t.  I gave it up, and as Kennedy seemed indisposed to enlighten me, I went for a stroll about the campus, returning as if drawn back to him by a lodestone.

About him was still the litter of test tubes, the photographs, the microscopes; and he was more absorbed in his delicate work than ever.

He looked up from his examination of a little glass slide and I could see by the crow’s feet in the corners of his eyes that he was not looking so much at me as through me at a very puzzling problem.

“Walter,” he remarked at length, “did you notice anything in particular about that blonde woman who dashed down the steps into the taxicab and escaped from the dope joint?”

“I should say that I did,” I returned, glad to ease my mind of what had been perplexing me ever since.  “I don’t want to appear to be foolish, but, frankly, I thought I had seen her before, and then when I tried to place her I found that I could not recognize her at all.  She seemed to be familiar, and yet when I tried to place her I could think of no one with just those features.  It was a foolish impression, I suppose.”

“That’s exactly it,” he exclaimed.  “I thought at first it was just a foolish impression, too, an intuition which my later judgment rejected.  But often those first impressions put you on the track of the truth.  I reconsidered.  You remember she had dropped that bandage from her face with the blood-stain on it.  I picked it up and it occurred to me to try a little experiment with these blood-stains which might show something.”

He paused a moment and fingered some of the microphotographs.

“What would you say,” he went on, “if I should tell you that a pronounced blonde, with a fair complexion and thin, almost hooked, nose, was in reality a negress?”