CHAIRMAN: PROFESSOR JAMES M. CRAFTS, Massachusetts Institute of Technology. SPEAKERS: PROFESSOR JOHN U. NEF, University of Chicago. PROFESSOR FRANK W. CLARKE, Chief Chemist, U. S. Geological Survey. SECTION A. INORGANIC CHEMISTRY. (_Hall 16, September 21, 10 a. m._) CHAIRMAN: PROFESSOR JOHN W. MALLET, University of Virginia. SPEAKERS: PROFESSOR HENRI MOISSAN, the Sorbonne; Member of the Institute of France. SIR WILLIAM RAMSAY, K.C.B., Royal Institution, London. SECRETARY: PROFESSOR WILLIAM L. DUDLEY, Vanderbilt University. SECTION B. ORGANIC CHEMISTRY. (_Hall 16, September 21, 3 p. m._) CHAIRMAN: PROFESSOR ALBERT B. PRESCOTT, University of Michigan. SPEAKERS: PROFESSOR JULIUS STIEGLITZ, University of Chicago. PROFESSOR WILLIAM A. NOYES, National Bureau of Standards. SECRETARY: SECTION C. PHYSICAL CHEMISTRY. (_Hall 16, September 22, 10 a. m._) CHAIRMAN: PROFESSOR WILDER D. BANCROFT, Cornell University. SPEAKERS: PROFESSOR J. H. VAN T'HOFF, University of Berlin. PROFESSOR ARTHUR A. NOYES, Massachusetts Institute of Technology. SECRETARY: MR. W. R. WHITNEY, Schenectady, N. Y. SECTION D. PHYSIOLOGICAL CHEMISTRY. (_Hall 16, September 22, 3 p. m._) CHAIRMAN: PROFESSOR WILDER O. ATWATER, Wesleyan University. SPEAKERS: PROFESSOR O. COHNHEIM, University of Heidelberg. PROFESSOR RUSSELL H. CHITTENDEN, Yale University. SECRETARY: DR. C. L. ALSBERG, Harvard University. DEPARTMENT 11--ASTRONOMY (_Hall 8, September 20, 4.15 p. m._) CHAIRMAN: PROFESSOR GEORGE C. COMSTOCK, Director of the Observatory, Madison, Wisconsin. SPEAKERS: PROFESSOR LEWIS BOSS, Director of Dudley Observatory. PROFESSOR EDWARD C. PICKERING, Director of Harvard Observatory. SECTION A. ASTROMETRY. (_Hall 9, September 21, 10 a. m._) CHAIRMAN: PROFESSOR ORMOND STONE, University of Virginia. SPEAKERS: DR. OSKAR BACKLUND, Director of the Observatory, Pulkowa, Russia. PROFESSOR JOHN C. KAPTEYN, University of Groningen, Holland. SECRETARY: PROFESSOR W. S. EICHELBERGER, U. S. Naval Observatory. SECTION B. ASTROPHYSICS. (_Hall 9, September 21, 3 p. m._) CHAIRMAN: PROFESSOR GEORGE E. HALE, Director of the Yerkes Observatory. SPEAKERS: PROFESSOR HERBERT H. TURNER, F.R.S., University of Oxford. PROFESSOR WILLIAM W. CAMPBELL, Director of The Lick Observatory, Mt. Hamilton, California. SECRETARY: MR. W. S. ADAMS, Yerkes Observatory. DEPARTMENT 12--SCIENCES OF THE EARTH (_Hall 3, September 20, 11.15 a. m._) CHAIRMAN: DR. G. K. GILBERT, U. S. Geological Survey. SPEAKERS: PROFESSOR THOMAS C. CHAMBERLIN, University of Chicago. PROFESSOR WILLIAM M. DAVIS, Harvard University. SECTION A. GEOPHYSICS. (_Hall 14, September 21, 10 a. m._)