From the moment when all belief in the spontaneous generation of the parasite is rejected, attention is naturally drawn to the possible consequences which may arise from burying in the earth animals which have died of splenic fever. In the greater number of cases, when the knacker's establishment is too far off and the dead animal is of little value, a trench is dug on the spot, at a depth varying from half a meter to a meter. If the animal dies in a field, it is buried where it falls; if it dies in a shed the body is carried into a neighbouring field. There it is buried, and putrefaction sets in; and since all the splenic fever filaments of the blood are destroyed by putrefaction, it was thought that no dissemination of the germs of splenic fever, after the animal had been buried, could occur. Pasteur showed that this opinion rested on a superficial observation. Even when the animal is not cut up, blood spreads itself outside of the body in more or less abundance. Is it not an habitual characteristic of the disease, that at the time of death blood issues from the nostrils and the mouth, and that the urine is often bloody? All around the corpse, therefore, the earth is polluted with blood. Moreover it takes several days for the splenic fever microbe to resolve itself into harmless granulations by the action of gases, other than oxygen, which putrefaction generates. During this time, the excessive inflation of the dead body causes the liquids of the interior to issue from all the natural apertures. How often also, a rent in the skin or the tissues increases this flow. The blood and other matters, mixed with the surrounding aerated soil, are no longer in the conditions of putrefaction, but rather in those which form a suitable medium of cultivation for the microbe. Experiments confirmed these views. Adding some splenic fever blood to earth sprinkled with the water of yeast, or with urine, at summer temperature, or at the temperature which the fermentation of a dead body keeps up around it, as in a dung heap, in less than twenty-four hours the splenic fever filaments deposited with the blood had multiplied and resolved themselves into spores. These spores were afterwards found in their state of latent life, ready to germinate and to communicate splenic fever, after remaining in the earth for months, and even years.