Page:The Sign of Four.pdf/108

Rh sardonicus," as the old writers called it, what conclusion would it suggest to your mind?'

'Death from some powerful vegetable alkaloid,' I answered, 'some strychnine-like substance which would produce tetanus.'

'That was the idea which occurred to me the instant I saw the drawn muscles of the face. On getting into the room I at once looked for the means by which the poison had entered the system. As you saw, I discovered a thorn which had been driven or shot with no great force into the scalp. You observe that the part struck was that which would be turned towards the hole in the ceiling if the man were erect in his chair. Now examine this thorn.'

I took it up gingerly and held it in the light of the lantern. It was long, sharp, and black, with a glazed look near the point as though some gummy substance had dried