Known as the Early Journal Content, this set of works include research articles, news, letters, and other writings published in more than 200 of the oldest leading academic journals. The works date from the mid--seventeenth to the early twentieth centuries. We encourage people to read and share the Early Journal Content openly and to tell others that this resource exists. People may post this content online or redistribute in any way for non--commercial purposes. Read more about Early Journal

more »

... ntent at http://about.jstor.org/participate--jstor/individuals/early-journal--content. JSTOR is a digital library of academic journals, books, and primary source objects. JSTOR helps people discover, use, and build upon a wide range of content through a powerful research and teaching platform, and preserves this content for future generations. JSTOR is part of ITHAKA, a not--for--profit organization that also includes Ithaka S+R and Portico. For more information about JSTOR, please contact support@jstor.org. 236 SCII electrical decompositions and of thermo-chemical data, or from even millions of the customary static chemical equations, would be like hoping to learn the nature of gravitation by laboriously weighing every moving object on the earth's surface, and recording the foot-pounds of energy given out when it fell. The simplest quantitative measure of gravity is, as every one knows, to determine it as the acceleration of a velocity: when we know the value of g, we are forever relieved, in the problem of falling bodies, from the necessity of weighing heterogeneous objects at the earth's surface, for they will all experience the same acceleration. May there not be something like this grand simplification to be discovered for chermical changes also ? The study of the speed of reaction has but just begun. It is a line of work surrounded with unusual difficulties, but it contains a rich store of promise. All other means for measuring the energies of chemism seem to have been tried except this: is it not, therefore, an encouraging fact, that to the chemists of the nineteenth century is left for exploration the great fruitful field of the true dynamics of the atom, the discovery of a time rate for the attractions due to affinity? THE MISSION OF SCIENCE.1 AFTER thanking the section for the honor conferred upon him by electing him their chairman, and referring to the success of the meeting of the British association at Montreal, Professor Thurston announced as the subject of his address, 'The mission of science.' He spoke of his address, as vice-president at St. Louis in 1878, on the philosophic method of the advancement of science, in which he had called attention to the need of specialists, amply supplied with the proper means, to do the work of observing, collecting, and co-ordinating the results of observation. As an all-important factor in this the modern system of scientific investigation, he had spoken of the men who have given, and who are still generously and liberally giving, material assistance by their splendid contributions to the scientific departments of our colleges and of our technical schools. It may well be asked, What is the use, and what is the object, of systematically gathering knowledge, and of constructing a great, an elaborate system, having the promotion of science as its sole end and aim? What is TI-E MISSION OF SCIENCE ? The great fact that material prosperity is the fruit of science, and that other great truth, that, as mankind is given opportunity for meditation and for culture, the higher attributes of human character are given development, are the best indications of the nature of the real mission of science, and of the correctness of the conclusion that the use and the aim of scientific inquiry 1 Abstract of an address to the section of mechanical science of the American association for the advancement of science at Philadelphia, Sept. 4, by Prof. R. H. THURSTON of Stevens institute, Hoboken, N.J., vice-president of the section. 236 SCII 1 Abstract of an address to the section of geology and geography of the American association for the advancement of science at Philadelphia, Sept. 4, by Prof. N. H. WINCHELL of the University of Minnesota, Minneapolis, Miinn., vice-president of the section. < <