congresses, having more or less reference to science, meeting at Paris during the present summer. Perhaps the most noteworthy of these, from the point of view of the organization of science, is the International Association of Academies, which was established last year at a conference held at Wiesbaden. In this Association eighteen of the great academies of the world, including our own National Academy of Sciences, have been united to promote the interests of science. Literature is also included— of the eighteen academies, twelve include in their scope both science and literature, four are devoted to science only and two to literature only. It is planned to have a general meeting every three years, to which each academy will send as many delegates as it regards as desirable, though each academy will have but one vote. In the interval between the general meetings, the business of the Association is to be directed by a committee, on which each academy is represented. The object of the Association is to plan and promote scientific work of international interest which may be proposed by one of the constituent academies, and generally to promote scientific relations between different countries. The Royal Society has proposed the measurement, by international coöperation, of an extended arc of the meridian in the interior of Africa.
The International Congress of Physics marked an advance owing to the fact that it met for the first time this year, and it appears that the proceedings were of unusual interest. This was in a large measure due to the arrangements of the French Physical Society, which did not simply make up a programme from a mass of heterogeneous researches, but secured some eighty reports on the present condition of physical science. These were prepared by many of the leading physicists of the world and when published—as they are about to be in three volumes—will set forth the condition of the science with completeness and authority. There were in all seven sections. In the first, which was concerned with measurement, in addition to numerous reports several propositions were brought forward in regard to units, which, being international in character, are specially fitted for discussion at such a congress. As the members, however, were not in most cases delegates from governments and scientific bodies, no definite action was taken, though some recommendations were made. The decimalization of time was not recommended, nor was the proposal to give a name to units of velocity and acceleration. It was, however, decided that the 'Barrie' be adopted as the unit of pressure. The other sections were for mechanical physics, for optics, for electricity, for magneto-optics and radio-activity, for cosmical physics and for biological physics. Among the reports and papers of commanding interest only two can be mentioned—the introductory address by M. Poincaré, discussing the relations between experimental and mathematical physics, and one by Lord Kelvin on the waves produced in an elastic solid traversed by a body acting on it by attraction or repulsion, in which, from a strictly mathematical point of view, he advanced the hypothesis of a movable atom surrounded by an immovable ether. In addition to various receptions, a session was held at the Sorbonne, where Messrs. Becquerel and Curie gave demonstrations with radioactive substances, and one at the Ecole Polytechnique, where President Cornu showed apparatus which had been used in the determination of the velocity of light. At the close of the congress the foreign secretaries placed a crown on the tomb of Fresnel.
While a physical congress was meeting at Paris this year for the first time, the Geological Congress, which was one of the first international congresses to be organized, held its eighth session, beginning on August 16. America, in spite of the number and