The principal point toward which inquiry must be directed is the question of pain. One reason why they have been partly condoned by the public is not difficult to discover. In language which seemed to have no element of ambiguity, the experimenter apparently affirmed the entire absence of sensation on the part of the dogs which he and his assistants subjected to operations of various kinds and of an extreme character. It is true that, as a general rule, this affirmation was not as explicit as might perhaps be desired. He was writing for professional men only, not for the general public, and it is quite unlikely that any physiologist or medical reader could have been at any time misled in the slightest degree. If the language used was capable of more than one interpretation, if possibilities of insensibility were exaggerated into definite assertions, nothing of the kind was apparent to the general reader. Glancing at the statement that "the animals were completely anaesthetized," his doubts were abolished. Indescribably disgusting and hideous as were some of the vivisections, if they were absolutely painless, their performance was a matter of taste. Can we criticize the humaneness of one who, at the butcher's bench, mutilates the body from which life has gone? Complete and perfect anaesthesia, maintained till death, is practically only premature death. Deprived of sensibility--a deprivation that is never to cease--a living creature is beyond the infliction of cruelty. But is it certain that all these various experiments, made upon nearly five hundred dogs were without pain? Reasons for doubt concerning some of them have been given. Let us now look into the question so far as concerns vivisection in its relation to the pressure of the blood. A little over two centuries ago the Rev. Stephen Hales, the rector of an obscure country parish in England, became interested in problems pertaining to the circulation of sap in plants, and blood in the higher animals. By various experiments he discovered that the blood of a living animal is subject to a definite pressure, and with some approach to accuracy he succeeded in measuring it. The subject seems to have attracted but little attention for over a century after the discovery of Hales; it was then again investigated by physiologists, and certain conclusions definitely reached. Without going into the subject at length, it suffices to state that this blood-pressure constantly varies slightly, being somewhat influenced by every disturbing condition, and probably by every physiological act. Any injury tending to lower the tone of the general system, or to induce the condition of shock, tends to cause the blood-pressure to fall. On the other hand, if the animal is sensible to pain, the stimulation of sensory nerves, or any sharp or sudden pang, TEND TO CAUSE A RISE IN THE PRESSURE OF THE BLOOD, unless the creature has become exhausted by the experimentation to which it has been subjected.