The International Geological Congress had its origin at Philadelphia in 1876, when, largely by the influence of Prof. Jas. Hall and Dr. Sterry Hunt, arrangements were made for a meeting of the Congress at Paris. This was held during the months of August and September, 1878, as one of a great series of International Congresses, embracing all branches of Science and the technical applications of the same. The full reports of these meetings are contained in 32 8vo. volumes; that on Geology forming No. 21 of the Series. In the Geological Congress papers were read and discussed on numerous subjects connected with the science.