to experiments on a dead animal, even though a sensitive mind, from association, shrinks from contemplating them. A person who dislikes the idea of dissecting a dead animal is influenced by purely subjective and personal considerations; nor is he prompted by sympathy with an unconscious animal when he recoils from the spectacle of its still moving organs. The term “vivisection” conveys too large a meaning. A negative term is needed, some word which will hold the emotion of pity in check. Pity is misplaced when devoted to the unconscious subjects of physiological experiment; and, happily for animals, as for Man, anæsthetics suspend conscious life. Only a person who has undergone a surgical operation can understand how resolutely the intellect declines to adopt as part of itself things which have not come within its own experience. The nurse’s testimony, that a long interval separated the placing of the mask upon the face and the commencement of that dull half-consciousness which gradually reawakened into interest in one’s surroundings cannot be set aside. The nurse says that during that interval knife, saw, and cautery were busy at their work. Her story is accepted, but it is not believed. All physiological operations are conducted under anæsthetics. In by far the larger number the experiment is continued until life terminates, under anæsthetics. The only ground upon which an objection to vivisection can be based is the ground that it involves the infliction of pain, and it is with regard to this that the greatest misapprehension exists in the public mind. Only in experiments which have for their object the study of the effects of the removal of a certain part, the diversion of a duct, the elimination of the control of a particular nerve, is there any possibility, under existing conditions, that an animal will suffer. In such experiments as these, observations cannot commence until after the animal has recovered. The operation is conducted under anæsthetics, and with the utmost precautions, to prevent any disturbance of the animal’s general health. The injury is in almost all cases of a comparatively limited nature, and it is certain that it involves very little pain to the animal when it has recovered from its anæsthesia, since, thanks this time to aseptic surgery, there is no inflammation or other secondary trouble. The field of physiology embraces the phenomena exhibited by all living things, whether plants or animals. The vegetable physiologist works in one part, the comparative physiologist in another. The work of the human physiologist is more limited in scope. Yet there are few problems relating to Man’s mechanism concerning which the physiologist can have direct knowledge. His theories are based upon the results obtained by experimenting upon animals. CHAPTER II THE BASIS OF LIFE