year of his membership. The fiftieth year would not strictly have occurred till 1876; but it was generally understood that he would have been elected in 1816, had he not urged the Academy to give the vacant place to M. Proust, who was old and infirm, and could not afford to wait. M. Dumas, the Permanent Secretary of the Academy, in a "gracefully-worded speech," recounted the many valuable services rendered by M. Chevreul, "the dean of French students," as he was modestly accustomed to style himself, and at the same time bore warm testimony to the personal character of the man. M. Élie de Beaumont, who had been a pupil of M. Chevreul, added a few words of veneration and respect for his old master, after which the latter, attempting to respond, could only express his inability to do so. In 1873 the Albert gold medal was awarded him by the English Society of Arts, for his valuable researches in connection with saponification, dyeing, agriculture, and natural history. In November, 1876, he was entertained at dinner by eighty savants in celebration of the fiftieth anniversary of his professorship and membership of the Academy of Sciences. The American Association for the Advancement of Science, at its Boston meeting in 1880, sent him a congratulatory telegram on his reaching his ninety-fifth year, and expressed the hope that he might be spared to continue his labors until the end of his century, which only a few months are lacking to see fulfilled. In the same year, he completed the fiftieth course of his lectures at the Museum, on the application of chemistry to organized bodies. Each course consisted of forty lectures, so that the fifty courses included in all two thousand lectures.
According to "Nature," M. Chevreul first important work was published in 1806. Among his other works than those we have already named, are one on organic analysis and its applications (1824); "Théorie des effets optiques que présentent les étoffes de soie" ("Theory of the Optical Effects presented by Silken Cloths," 1848); "De la baguette divinatoire, du pendule, et des tables tournantes" ("Of the Divining-Rod, the Pendulum, and Turning-Tables," 1854); "The History of Chemical Science," of which the first volume was published in 1866; "Memoirs of the Academy," completed in 1872, "a most interesting work, which throws light on many of the most scientific questions of the day"; and numerous papers, articles in encyclopædias, and books of less general interest than those mentioned. A curious illustration of his vigor and activity, lasting into extreme old age, is afforded by a communication which he made to the Academy of Sciences on the 4th of February, 1884, which was on the varying color-effects produced by the glare of a conflagration playing upon a gas-light that stood in front of the Museum, which he observed for an hour. Delicate work that for the eyes of a man ninety-eight years old! That vigor still continued till the beginning of the present year, when M. Chevreul presided at the meeting of the new