Describing the experiments of Prof. Hertz, of Carlsruhe, and other investigators, he declared it certain that all radiant energy is transmitted as electromagnetic waves in luminiferous ether. In the Chemical Section, Prof. W, L. Dudley, of Vanderbilt University, Nashville, chose amalgams as his subject. His treatment was clear and suggestive, but of necessity technical. Mr. R. S. Woodward, mathematician to the United States Geological Survey, Washington, presided over the section of Mathematics and Astronomy. His address on mathematical theories of the earth was a successful endeavor to make clear to hearers, scientific and unscientific, the history of a theme usually wrapped up in the rigid mummy-cloths of mathematical formulæ.
Among the more noteworthy contributions to the various sections we may mention, in Section A, the paper of Prof. J. E. Eastman, of the Washington Observatory, on stellar distances. He argued that no relation exists between the magnitudes, distances, and proper motions of stars. Prof. Charles Carpmael made a plea for numbering the hours of the day from one to twenty-four, abolishing the necessity for writing a. m. and p. m. The plan has been adopted by the Canadian Pacific Railway on its Western and Pacific divisions. In accordance with Prof. Carpmael's suggestion, the Association memorialized the Governments of the United States and Canada, of the various States of the Union, and provinces of the Dominion. Much interest was developed in the exhibition of the Hastings achromatic objective, one of the notable gifts of mathematical and mechanical science to astronomy. It promotes accuracy of definition twenty-three per cent, and eliminates spherical aberration. In Section B, Prof. Thomas Gray, of the Rose Polytechnic Institute, Terre Haute, gave an experimental demonstration of methods of electrical measurement. Dr. George F. Barker, of the University of Pennsylvania, reviewed recent improvements in electrical storage batteries. He showed the immense advance in efficiency gained in the newest batteries based on the Planté model. In Section C, Mr. Charles E. Monroe, of Newport, E. I., gave the results of investigation into the explosiveness of celluloids. He had found the opaque variety insensitive to a shock of detonation at ordinary temperatures, while translucent celluloids were readily exploded by this means. Mr. O. Chanute, of Chicago, who has made the subject a specialty, gave an account of the best methods for preserving timber. After discussing the question of weights and measures. Section C passed a resolution urging colleges of pharmacy and medicine to adopt the metric system. Before Section E, the Society of American Geologists held a session, at which Prof. James D. Dana, of Yale, took occasion, in the light of new geological discoveries, to revise certain of his former teachings respecting areas of continental progress. Among his suggestions in nomenclature was that Ontarian be substituted for Silurian in local geological phraseology. In Section E, Rev. H. C. Hovey, of Bridgeport, Conn., described the newly explored pits of remarkable depth in the Mammoth Cave of Kentucky; the whole series of pits being connected by a magnificent hall several hundred feet in length. Mr. E. T. Hill, of the State Geological Survey of Texas, read several excellent papers on the general features of Texan geology, on the Eagle Flats of the mountainous region of Texas, the ancient volcanoes and Staked Plains of the State. In Section F a good many papers of value were read—all, however, technical in character. Prof. C. V. Riley, entomologist to the United States Department of Agriculture at Washington, contributed a paper on the best methods of subduing injurious insects by intentional importation of their natural enemies. Much interest
