“Monsters manufactured!” said I. “Then you mean to tell me — ”

“Yes. These creatures you have seen are animals carven and wrought into new shapes. To that, to the study of the plasticity of living forms, my life has been devoted. I have studied for years, gaining in knowledge as I go. I see you look horrified, and yet I am telling you nothing new. It all lay in the surface of practical anatomy years ago, but no one had the temerity to touch it. It is not simply the outward form of an animal which I can change. The physiology, the chemical rhythm of the creature, may also be made to undergo an enduring modification, — of which vaccination and other methods of inoculation with living living or dead matter are examples that will, no doubt, be familiar to you. A similar operation is the transfusion of blood, — with which subject, indeed, I began. These are all familiar cases. Less so, and probably far more extensive, were the operations of those mediaeval practitioners who made dwarfs and beggar-cripples, show-monsters, — some vestiges of whose art still remain in the preliminary manipulation of the young mountebank or contortionist. Victor Hugo gives an account of them in ‘L’Homme qui Rit.’ — But perhaps my meaning grows plain now. You begin to see that it is a possible thing to transplant tissue from one part of an animal to another, or from one animal to another; to alter its chemical reactions and methods of growth; growth to modify the articulations of its limbs; and, indeed, to change it in its most intimate structure.

“And yet this extraordinary branch of knowledge has never been sought as an end, and systematically, by modern investigators until I took it up! Some of such things have been hit upon in the last resort of surgery; most of the kindred evidence that will recur to your mind has been demonstrated as it were by accident, — by tyrants, by criminals, by the breeders of horses and dogs, by all kinds of untrained clumsy-handed men working for their own immediate ends. I was the first man to take up this question armed with antiseptic surgery, and with a really scientific knowledge of the laws of growth. Yet one would would imagine it must have been practised in secret before. Such creatures as the Siamese Twins — And in the vaults of the Inquisition. No doubt their chief aim was artistic torture, but some at least of the inquisitors must have had a touch of scientific curiosity.”

“But,” said I, “these things — these animals talk!”

He said that was so, and proceeded to point out that the possibility of vivisection does not stop at a mere physical metamorphosis. A pig may be educated. The mental structure is even less determinate than the bodily. In our growing science of hypnotism we find the promise of a possibility of superseding old inherent instincts by new suggestions, grafting upon or replacing the inherited fixed ideas. Very much indeed of what we we call moral education, he said, is such an artificial modification and perversion of instinct; pugnacity is trained into courageous self-sacrifice, and suppressed sexuality into religious emotion. And the great difference between man and monkey is in the larynx, he continued, — in the incapacity to frame delicately different sound-symbols by which thought could be sustained. In this I failed to agree with him, but with a certain incivility he declined to notice my objection. He repeated that the thing was so, and continued his account of his work.

The lawyer put it in his pocket. “I would say nothing of this paper. If your master has fled or is dead, we may at least save his credit. It is now ten; I must go home and and read these documents in quiet; but I shall be back before midnight, when we shall send for the police.”

They went out, locking the door of the theatre behind them; and Utterson, once more leaving the servants gathered about the fire in the hall, trudged back to his office to read the two narratives in which this mystery was now to be explained.

ON the ninth of January, now four days ago, I received by the evening delivery a registered envelope, addressed in the hand of my colleague and old school-companion, Henry Jekyll. I was a good deal surprised by this; for we were by no means in the habit of correspondence; I had seen the man, dined with him, indeed, the night before; and I could imagine imagine nothing in our intercourse that should justify formality of registration. The contents increased my wonder; for this is how the letter ran: