Maitland stared back blankly into the Doctor's smiling eyes for a moment, then looked long at the penknife on the floor, and finally stooped and cautiously took it between his forefinger and thumb, eyeing it doubtfully the while. Then he suddenly sat down, pulled out his pocket handkerchief, and mopped off the perspiration that freely bedewed his face. "Well, I'll be shot!" he ejaculated. "What an extraordinary experience! Will you believe me, Doctor, when I tell you that as I drew this penknife out of my waistcoat pocket it actually seemed to change into an adder in my hand? There was the flat, wicked-looking head, the malevolent eyes, the characteristic markings of the body, and, above all, there was the feeling of it writhing strongly in my grasp, as though it were trying to get enough of its length clear to turn and strike me! Talk about Aaron's rod and those of the old Egyptian necromancers turning into serpents! Why, I could have sworn that this knife of mine did precisely the same thing! Now, there is a problem for you, Doctor: What sort of mental aberration was it that caused me to imagine such an extraordinary thing as that, eh?" "Simply, my dear boy, that I hypnotised you `unbeknownst', so to speak, in illustration of what I have been telling you," answered the Doctor, laying his hand upon Dick's shoulder. "Hope I didn't scare you very severely, eh?" "N-o," answered Dick slowly, "you did not actually scare me, Doctor; but you managed to give me such a thrill of horror and disgust as I have not experienced for many a long day. But, I say, do you really mean to tell me, in sober earnest, that that abominable experience was due to hypnotic suggestion on your part?" "Yes, I do," answered Humphreys. "I wanted to bring home to you in a very convincing manner the power which the hypnotist exercises over his subject. I could have done it even more convincingly, perhaps, by commanding you to take that perfectly cold poker in your hand, and then suggesting to you that it was red hot, when--despite the fact of the poker being cold--your hand would have been most painfully blistered. But probably the `adder' experiment was convincing enough, eh?" "It was indeed," assented Dick with a little reminiscent shudder. "But look here, Doctor, you say that you hypnotised me. When did you do it? I didn't see you do anything peculiar."