popular lecturer, and bowed politely to his audience.

“Messieurs, mesdames, as you all know, I was called in by Monsieur John Cavendish to investigate this case. I at once examined the bedroom of the deceased which, by the advice of the doctors, had been kept locked, and was consequently exactly as it had been when the tragedy occurred. I found: first, a fragment of green material; second, a stain on the carpet near the window, still damp; thirdly, an empty box of bromide powders.

“To take the

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