story to the building in 1855, when part of the library was moved into it, and the weekly meetings were held there until the removal to South Logan Square.
In 1876, By-Laws were adopted providing for the appointment of thirteen professors, each with authority to appoint one or more assistants. A number of these positions were filled and acceptable courses of lectures were delivered by J. Gibbons Hunt on histology and microscopic technology; by Henry Carvill Lewis, on mineralogy; by Angelo Heilprin, on invertebrate paleontology and geology; by Benjamin Sharp, on lower invertebrata, and by Daniel G. Brinton, on ethnology and archeology. These courses were well attended, and were, under the energetic management of the Rev. Dr. McCook as chairman of the Committee on Instruction and Lectures, productive of excellent results, but none of them secured sufficient return for the adequate compensation of the professors, and, in the absence of endowments, the By-Laws defining the positions were subsequently repealed.
Courses of popular evening lectures were delivered successfully during the winters of 1887 to 1895. In 1896 a proposition was made by the Ludwick Institute that the Committee on Instruction should cooperate with the Institute in arranging a course of lectures on natural science and allied subjects, to be given in the Academy's lecture hall and to be free to the public though primarily for the benefit of public school teachers, the Ludwick Institute bearing all expenses. Under this arrangement six to eight courses have been given annually by members of the society, the courses for the session of 1908-1909 being as follows: Seneca Egbert, A.M., M.D., "The Prevention of Disease and the Preservation of Health;" J. Percy Moore, Ph.D., "Illustrations of the Life Histories and Habits of the Lower Animals;" Spencer Trotter, M.D., "Anthropology and Ethnology;" Henry A. Pilsbry, Sc.D., "Shell Fish (Mollusks);" Witmer Stone, A.M., "Studies in Local Bird Life;" T. M. Lightfoot, M.S., Ph.D., "Economic Geology;" Stewardson Brown, "Wild Flowers and Seasons;" Henry Skinner, M.D., "Geographical Distribution of Insects."
The following officers were elected at the annual meeting to serve during 1909:
President, Samuel G. Dixon, M.D., LL.D.; Vice-Presidents, Arthur Erwin Brown, Sc.D. and Edwin G. Conklin, Ph.D.; Recording Secretary and Librarian, Edward J. Nolan, M.D.;
