“What, indeed? It is art for art’s sake, Watson. I suppose when you doctored you found yourself studying cases without thought of a fee?”

“For my education, Holmes.”

“Education never ends, Watson. It is a series of lessons with the greatest for the last. This is an instructive case. There is neither money nor credit in it, and yet one would wish to tidy it up. When dusk comes we should find ourselves one stage advanced in our investigation.”

When we returned to Mrs. Warren’s rooms, the gloom of a London winter evening had thickened into one gray curtain, a dead monotone of colour, broken only by the sharp yellow squares of the windows and the blurred haloes of the gas-lamps. As we peered from the darkened sitting-room of the lodging-house, one more dim light glimmered high up through the obscurity.