Through all Pasteur’s anxieties about the war, certain observations, certain projected experiments resounded in his mind like the hours that a clock strikes, unheeded but not unheard, in a house visited by death. He could not put them away from him, they were part of his very life. Any sort of laboratory work was difficult for him in the tanner’s house, which had remained the joint property of himself and his sister. His brother-in-law had continued Joseph Pasteur’s trade. Pasteur applied his spirit of observation to everything around him, and took the opportunity of studying the fermentation of tan. He would ask endless questions, trying to discover the scientific reason of every process and every routine. Whilst his sister was making bread he would study the raising of the crust, the influence of air in the kneading of the dough, and his imagination rising as usual from a minor point to the greatest problems, he began to seek for a means of increasing the nutritive powers of bread, and consequently of lowering its price. The _Salut Public_ of December 20 contained a notice on that very subject, which Pasteur transcribed. The Central Commission of Hygiene which included among its members Sainte Claire Deville, Wurtz, Bouchardat and Trélat, had tried, when dealing with this question of bread (a vital one during the siege), to prove to the Parisians that bread is the more wholesome for containing a little bran. “With what emotion,” wrote Pasteur, “I have just read all those names dear to science, greater now before their fellow-citizens and before posterity. Why could I not share their sufferings and their dangers!” He would have added “and their work” if some of the Académie des Sciences reports had reached him. The history of the Academy during the war is worthy of brief mention. Moreover it was too deeply interesting to Pasteur, too constantly in his thoughts, not to be considered as forming part of his biography. During the first period, the Academy, imagining, like the rest of France, that there was no doubt of a favourable issue of the war, continued its purely scientific task. When the first defeats were announced, the habitual communications ceased, and the Academy, unable to think of anything but the war, held sittings of three-quarters of an hour or even less.