He joined the Chemical Society in 1855, and was a member of its Council in 1860-1864, and again in 1871-1873. He was a Vice-President in 1873-1875, and again in 1877-1880, and was President from 1880 to 1882. His two presidential addresses, “abstracts and brief chronicles of the time,” dealt mainly with the results of chemical inquiry during the preceding year, especially in relation to the inorganic section of the science. On the first occasion it fell to his duty to refer to the death of Sir Benjamin C. Brodie, a former secretary and president of the Society, whose friendship, as his autobiography testifies, he valued “as that of a true, generous, and noble-hearted man.” Roscoe was the Mæcenas of the Chemical Society. Indeed, he may be said to have resembled that grand seigneur in the simplicity and cordiality which, as the poet tells us, characterized his relations to the men of his circle. Certainly no Fellow of the Society ever showed himself a more beneficent or more generous patron. The walls of its rooms bear witness to his kindly thought and constant remembrance. Its library has been augmented by gifts from him of close upon a thousand volumes, including rare alchemical and early chemical works, and of complete sets of some of the most valuable of the serial publications of the science. It was in grateful recognition of this liberal and warm-hearted encouragement of the objects for which the Society was instituted that his old pupils resolved to commemorate his connection with it by placing, on the occasion of his eightieth birthday, his bust in the library which he had done so much to enrich, and at the same time to offer a replica of Mr. Drury’s admirable work to his family. Roscoe was one of the original members of the Society of Chemical Industry, and took a leading part in establishing it on its present basis as a national institution, with local sections in many of our principal towns, and branches in certain of our colonies, and in America. How it originated may be gleaned from the following letter. There had been a previous attempt to establish a local society with special reference to the South Lancashire district. But Roscoe, with others of its projectors, had conceived the idea of placing it on a wider plane, and the meeting referred to was called to ascertain the general feeling as to the expediency of the action. THE OWENS COLLEGE, MANCHESTER, _April 13, ’80_. We are going to have a meeting _here_ on Monday next, at 7 p.m., of chemical manufacturers and others, to consider the question of the establishment of a Lancashire Chemical Society, or of a more General Institute or Society of Chemical Engineers. If you can come over I should be very glad, as it is likely to be an important meeting and your opinion would be of value.