Transactions (continued). Halle :- Houghton :-Michigan Mining School. 8vo. Halle 1894; Halle 1894. The Academy. Catalogue. 1892-94. The School. Uchenuiya Zapiski (Scientific Notes). 1895. No. 3. 8vo. Kazan. 、 La Plata :—Museo. Anales: Paleontología Argentina. Tomo III. Folio. La Plata 1894. The Museum. London :-British Astronomical Association. Journal. No. 6. 8vo. London 1895. Vol. V. The Association. City and Guilds of London Institute. Report to the Governors. London Mathematical Society. Proceedings. The Institute. Vol. XXVI. Nos. The Society. Quekett Microscopical Club. Journal. Vol. VI. No. 36. 8vo. The Club. Royal Microscopical Society. Journal. 1895. Part 2. 8vo. London. The Society. Royal United Service Institution. Journal. April, 1895. Svo. Moscow :-Société Impériale des Naturalistes. Bulletin. 1894. No. 4. 8vo. Moscou 1895. The Society. Nantes :-Société des Sciences Naturelles de l'Ouest de la France. New York:-American Museum of Natural History. Bulletin. Paris-Société d'Encouragement pour l'Industrie Nationale. Annuaire. 1895. 12mo. Paris. The Museum. The Society. Tome VI. No. 4. 8vo. The Society. Transactions (continued). St. Petersburg:-Académie Impériale des Sciences. Bulletin. San Francisco:-California Academy of Sciences. Proceedings. Santiago:-Sociedad Nacional de Mineria. The Academy. Boletin. Año XI. The Society. Vol. VII. Fasc. No. 75. 4to. Santiago de Chile 1894. Siena :-R. Accademia dei Fisiocritici. Atti. 1, 2. 8vo. Siena 1895; Processi Verbali. mico 203. No. 7. Anno Accademico 204. Nos. 1, 2. 8vo. Siena 1895. Anno Accade The Academy. Würzburg; Ver Würzburg-Physikalisch-medicinische Gesellschaft. Berichte. Jahrg. 1894. Nos. 8-10. 8vo. handlungen. Bd. XXVIII. Nos. 6, 7. 8vo. Zurich : Naturforschende Gesellschaft. Observations and Reports. Würzburg 1894. Vierteljahrsschrift. The Bureau. Austria -K.K. Gradmessungs-Bureau. Astronomische Arbeiten. London :-Local Government Board. Cholera in England in 1893. 8vo. The Department. Reports and Papers on London 1894. The Medical Officer. Melbourne :-Centennial International Exhibition, 1888. Catalogue of the Exhibits in the Queensland Court. 8vo. Brisbane 1888; Catalogue of the Minerals in the Queensland Court. 8vo. Brisbane 1888. Messrs. Williams and Norgate. Mersey:-Report on the Present State of the Navigation of the River Mersey. 1894. 8vo. London 1895. Adm. Sir G. H. Richards, F.R.S. Oxford: Radcliffe Library. Catalogue of Books added during the year 1894. 8vo. Oxford 1895. The Trustees. St. Petersburg :-Physikalisches Central-Observatorium. Annalen. Jahrg. 1893. Theil 2. 4to. St. Petersburg 1894. The Observatory. Observations and Reports (continued). U.S. Coast and Geodetic Survey. Bulletin. Nos. 31-33. 8vo. The Commission. U.S. Department of Agriculture. Experiment Station Record. Vol. V. No. 12. Vol. VI. Nos. 2, 3, 5. 8vo. Washington 1894-95; Report of the Secretary. 1893. 1894. 8vo. Washington The Department. Journals. Annaes de Sciencias Naturaes. Anno II. No. 2. 8vo. Porto 1895. The Editor. Archives Néerlandaises des Sciences Exactes et Naturelles. Tome XXIX. Livr. 1. 8vo. Harlem 1895. Société Hollandaise des Sciences. Jahresbericht über die Fortschritte in der Lehre von den Gährungs-Organismen. Jahrg. IV. 8vo. Braunschweig 1894. The Publisher. Medico-Legal Journal. Vol. XII. No. 3. 8vo. New York 1894. The Editor. Mittheilungen aus der Zoologischen Station zu Neapel. Bd. XI. Heft 4. 8vo. Berlin 1895. The Station. Zeitschrift für Biologie. Bd. XXXII. Heft 1. 8vo. München 1895. The Editors. Bedell (F.) and Ryan (H. J.) Action of a Single-phase Synchronous Motor. 8vo. 8vo. Philadelphia 1895. The Authors. Braithwaite (R.) The British Moss-Flora. Part XVI. 4to. London 1895. The Author. Iwanzoff (N.). Der mikroskopische Bau des elektrischen Organs von Torpedo. 8vo. Moskau 1895; [and two Excerpts. 8vo.] The Author. Jörgensen (A.) Der Ursprung der Weinhefen. 8vo. Jena 1895. The Author. Kölliker (A. v.), For. Mem. R.S. Kritik der Hypothesen von Rabl- The Author. R. Istituto Tecnico, Florence. Wilde (H.), F.R.S. On the Evidence afforded by Bode's Law of a permanent Contraction of the Radii Vectores of the Planetary Orbits. 8vo. Manchester 1895; on the Multiple Proportions of the Atomic Weights of Elementary Substances in relation to the Unit of Hydrogen. 8vo. Manchester 1895. The Author. May 9, 1895. The LORD KELVIN, D.C.L., LL.D., President, in the Chair. A List of the Presents received was laid on the table, and thanks ordered for them. The Bakerian Lecture was delivered as follows: BAKERIAN LECTURE.-" On the Laws of Connexion between the Conditions of Chemical Change and its Amount." By A. VERNON HARCOURT, M.A., F.R.S., Student of Christ Church, and Lee's Reader in Chemistry, and WILLIAM ESSON, M.A., F.R.S., Fellow of Merton College, and Deputy Savilian Professor of Geometry in the University of Oxford. "III. Further Researches on the Reaction of Hydrogen Dioxide and Hydrogen Iodide." Received March 15, 1895. (Abstract.) In this paper are considered the effect upon the reaction of (1) substances not directly participating in it, (2) temperature. A short description is given of the manner in which the observations were made. The equation which expresses the result of a single set of observations was shown in a previous paper to be are the amounts of potential change at the times to, t1 respectively. Each set of observations gives a mean value of a, which is taken to be the value of the rate of change under the conditions of the set. The effect of the variation of the conditions upon the value of considered to be a measure of their effect upon the course of the reaction. Variation of Hydrogen Sulphate. α is It is shown from the results of three sets of experiments at temperatures of 16°, 20°, and 30°, that the increment in the value of the |