Pasteur, like a general with only two aides de camp, was obliged to direct the efforts of Messrs. Chamberland and Roux simultaneously in different parts of France. Sometimes facts had to be checked which had been over-hastily announced by rash experimentalists. Thus M. Roux went, towards the end of the month of July, to an isolated property near Nancy, called Bois le Duc Farm, to ascertain whether the successive deaths of nineteen head of cattle were really, as affirmed, due to splenic fever. The water of this pasture was alleged to be contaminated; the absolute isolation of the herd seemed to exclude all idea of contagion. After collecting water and earth from various points on the estate M. Roux had returned to the laboratory with his tubes and pipets. He was much inclined to believe that there had been septicæmia and not splenic fever. M. Chamberland was at Savagna, near Lons-le-Saulnier, where, in order to experiment on the contamination of the surface of pits, he had had a little enclosure traced out and surrounded by an open paling in a meadow where victims of splenic fever had been buried two years previously. Four sheep were folded in this enclosure. Another similar fold, also enclosing four sheep, was placed a few yards above the first one. This experiment was intended to occupy the vacation, and Pasteur meant to watch it from Arbois. A great sorrow awaited him there. “I have just had the misfortune of losing my sister,” he wrote to Nisard at the beginning of August, “to see whom (as also my parents’ and children’s graves) I returned yearly to Arbois. Within forty-eight hours I witnessed life, sickness, death and burial; such rapidity is terrifying. I deeply loved my sister, who, in difficult times, when modest ease even did not reign in our home, carried the heavy burden of the day and devoted herself to the little ones of whom I was one. I am now the only survivor of my paternal and maternal families.” In the first days of August, Toussaint, the young professor of the Toulouse Veterinary School, declared that he had succeeded in vaccinating sheep against splenic fever. One process of vaccination (which consisted in collecting the blood of an animal affected with charbon just before or immediately after death, defibrinating it and then passing it through a piece of linen and filtering it through ten or twelve sheets of paper) had been unsuccessful; the bacteridia came through it all and killed instead of preserving the animal. Toussaint then had recourse to heat to kill the bacteridia: “I raised,” he said, “the defibrinated blood to a heat of 55° C. for ten minutes; the result was complete. Five sheep inoculated with three cubic cent. of that blood, and afterwards with very active charbon blood, have not felt it in the least.” However, several successive inoculations had to be made.