"Did you observe anything very peculiar about that bed?" Holmes demanded. "It was clamped to the floor. Did you ever see a bed fastened like that before?"

"I cannot say that I have."

"The lady could not move her bed. It must always be in the same relative position to the ventilator and to the rope - or so we may call it, since it was clearly never meant for a bell-pull."

"Holmes," I cried, "I seem to see dimly what you are hinting at. We are only just in time to prevent some subtle and horrible crime."

"Subtle enough and horrible enough. When a doctor does go wrong he is the first of criminals. He has nerve and he has knowledge. Palmer and Pritchard were among the worst in their profession. This man strikes even deeper. But I think, Watson, that we shall be able to strike deeper still. But we shall have horrors enough before the night is over; for goodness' sake let us have a quiet pipe and turn our minds for a few hours to something more cheerful." you?"