"Smith!" I whispered huskily--"God forgive me, what have I done? What have I done?" I stepped forward to support him ere he fell; but utter oblivion closed down upon me, and I knew no more. * * * * * * * "He will do quite well now." said a voice that seemed to come from a vast distance. "The effects of the drug will have entirely worn off when he wakes, except that there may be nausea, and possibly muscular pain for a time." I opened my eyes; they were throbbing agonizingly. I lay in bed, and beside me stood Murdoch McCabe, the famous toxicological expert from Charing Cross Hospital--and Nayland Smith! "Ah, that's better!" cried McCabe cheerily. "Here--drink this." I drank from the glass which he raised to my lips. I was too weak for speech, too weak for wonder. Nayland Smith, his face gray and drawn in the cold light of early morning, watched me anxiously. McCabe in a matter of fact way that acted upon me like a welcome tonic, put several purely medical questions, which at first by dint of a great effort, but, with ever-increasing ease, I answered. "Yes," he said musingly at last. "Of course it is all but impossible to speak with certainty, but I am disposed to think that you have been drugged with some preparation of hashish. The most likely is that known in Eastern countries as _maagûn_ or _barsh_, composed of equal parts of _cannabis indica_ and opium, with hellebore and two other constituents, which vary according to the purpose which the _maagûn_ is intended to serve. This renders the subject particularly open to subjective hallucination, and a pliable instrument in the hands of a hypnotic operator, for instance." "You see, old man?" cried Smith eagerly. "You see?" But I shook my head weakly. "I shot you," I said. "It is impossible that I could have missed." "Mr. Smith has placed me in possession of the facts," interrupted McCabe, "and I can outline with reasonable certainty what took place. Of course, it's all very amazing, utterly fantastic in fact, but I have met with almost parallel cases in Egypt, in India, and elsewhere in the East: never in London, I'll confess. You see, Dr. Petrie, you were taken into the presence of a very accomplished hypnotist, having been previously prepared by a stiff administration of _maagûn_. You are doubtless familiar with the remarkable experiments in psycho-therapeutics conducted at the Salpêtrier in Paris, and you will readily understand me when I say that, prior to your recovering consciousness in the presence of the mandarin Ki-Ming, you had received your hypnotic instructions. "These were to be put into execution either at a certain time (duly impressed upon your drugged mind) or at a given signal...." "It was a signal," snapped Smith. "Ki-Ming stood in the court below and looked up at the window," I objected. "In that event," snapped Smith, "he would have spoken softly, through the letter-box of the door!"