It is also to such boards that living animals are fastened when it is necessary to experiment upon them. Certainly when one sees a dog lying with a forlorn look, its feet tied, its body trembling from fright, on the point of undergoing, though in full health, a bloody operation, one cannot suppress the feelings of pity. But a single visit to a physiological laboratory suffices to reveal vivisection in its only and true light; that of the interest it offers to science, and the results it may have in store for the benefit of humanity. Moreover, in Pasteur's laboratory, every dog subjected to vivisection is chloroformed. The persons who take up the controversy about vivisection are careful that the outside world shall see only the suffering and anguish of the animal, where the solution of a problem should be the object kept in view. Would the English physiologist Harvey have discovered the circulation of the blood, if he had not practised vivisection on deer in the park of Charles I.? Would Claude Bernard have been able, without vivisection, to demonstrate the glycogenic function of the liver? If Pasteur had not sacrificed some fowls and sheep, would the great scientific fact of the attenuation of virus have been discovered? If 500 dogs had to perish, what would that be, compared with the discovery tomorrow of the cause of hydrophobia, and of the means of protecting humanity against this frightful scourge? On one occasion, in presence of a large assembly, Pasteur made an experiment on atmospheric oxygen. He placed under a glass bell a bird, which in a short time, after having consumed the oxygen contained in the bell, gathered itself up into a ball, opened its beak, and shut its eyes, as if it were going to die. At this moment Pasteur introduced a second sparrow, which, passing directly from the ordinary air into the bell, without any gradual preparation, immediately fell, asphyxiated. There was a little exclamation of horror and a movement of pity in the audience. While the first sparrow, which had gone through the ordeal unharmed, was set free, and gradually revived, Pasteur turned towards the assembly and said-- 'I never had the courage to kill a bird in sport, but when it is a question of experiment I am deterred by no scruple. Science has the right to assert the sovereignty of its aims.' * * * * *