A reception somewhat similar to that given to Villemin was reserved for Davaine, who, having meditated on Pasteur’s works on butyric ferment and the part played by that ferment, compared it and its action with certain parasites visible with a microscope and observed by him in the blood of animals which had died of charbon disease. By its action and its rapid multiplication in the blood, this agent endowed with life probably acted, said Davaine, after the manner of ferments. The blood was modified to that extent that it speedily brought about the death of the infected animal. Davaine called those filaments found in anthrax “bacteria,” and added, “They have a place in the classification of living beings.” But what was that animated virus to many doctors? They answered experimental proofs by oratorical arguments. At the very time when Pasteur took his seat at the Academy of Medicine, Davaine was being violently attacked; his experiments on septicæmia were the cause, or the pretext. But the mere tone of the discussions prepared Pasteur for future battles. The theory of germs, the doctrine of virus ferments, all this was considered as a complete reversal of acquired notions, a heresy which had to be suppressed. A well-known surgeon, Dr. Chassaignac, spoke before the Académie de Médecine of what he called “laboratory surgery, which has destroyed very many animals and saved very few human beings.” In order to remind experimentalists of the distance between them and practitioners, he added: “Laboratory results should be brought out in a circumspect, modest and reserved manner, as long as they have not been sanctioned by long clinical researches, a sanction without which there is no real and practical medical science.” Everything, he said, could not be resolved into a question of bacteria! And, ironically, far from realizing the truth of his sarcastic prophecy, he exclaimed, “Typhoid fever, bacterization! Hospital miasma, bacterization!” Every one had a word to say. Dr. Piorry, an octogenarian, somewhat weighed down with the burden of his years and reputation, rose to speak with his accustomed solemnity. He had found for Villemin’s experiments the simple explanation that “the tuberculous matter seems to be no other than pus, which, in consequence of its sojourn in the organs, has undergone varied and numerous modifications”; and he now imagined that one of the principal causes of fatal accidents due to septicæmia after surgical operations was the imperfect ventilation of hospital wards. It was enough, he thought, that putrid odours should not be perceptible, for the rate of mortality to be decreased. It was then affirmed that putrid infection was not an organized ferment, that inferior organisms had in themselves no toxic action, in fact, that they were the result and not the cause of putrid alteration; whereupon Dr. Bouillaud, a contemporary of Dr. Piorry, called upon their new colleague to give his opinion on the subject.