Three Presidential addresses, delivered recently in this country and abroad, give admirable surveys of the present status, of past growth and of the future needs of chemistry. The address of Professor F. W. Clarke to the American Chemical Society, given December 30, 1901, on 'The Development of Chemistry' deals with the four principal agencies that have been instrumental in building the chemical structure of to-day; these are: private enterprise, the commercial demand, governmental requirements, and university teaching. At the beginning all these agencies had not been established, the two great stimuli to chemical research were the intellectual interest of the problem to be solved, and practical utility; these still have great influence, but the most important need at the present time, says Professor Clarke, is a well equipped and endowed research laboratory, in which to conduct systematic and thorough investigations.
Dr. Ira Remsen chose for his address to the same society, given a year later, 'The Life History of a Doctrine.' In a scholarly and witty way he sketched the early history, development and modern phases of the atomic theory, saying that in the light of late advances we must enlarge our conception of atoms. He pointed out that the many obituaries on the electrochemical theory of Berzelius were probably premature, since in the latest conception of atoms electrical charges play an important part. An atom charged with electricity is called an ion, and only then is it ready for action. At the same time President Remsen refers to physicists the explanation of some of the features of the theory of ions.
Professor James Dewar, in his address as president of the British Association for the Advancement of Science, delivered September 10, 1902, was of a more comprehensive nature, reviewing many aspects of science. Incidentally he compared the chemical equipments of England and Germany to the decided disadvantage of the former, stating that Germany possessed a professional staff one third larger in numbers and superior in quality. One firm in Germany, employing 5,000 workmen, has a staff of 160 chemists, 260 mechanics and engineers, besides 680 clerks. Owing to the high education and practical character of their chemists German manufacturers enjoy a monopoly. Passing from this theme, Professor Dewar gave some of the interesting results obtained in his researches on low temperatures, especially in liquefying hydrogen and helium. The whole address, which is very readable, can be found in the October numbers of Science. Besides these addresses another one by Dewar must not be overlooked, the 'Centenary Commemoration Lecture' at the Royal Institution.
The Bi-Centennial of Yale University, celebrated in 1901, was appropriately marked by the publication of several superb volumes containing chemical research conducted by professors and instructors in that institution. Two of these are from the Kent Chemical Laboratory, and embody the labors of Professor F. A. Gooch, and of some of his assistants; the other two are from the Sheffield Scientific School, and contain chiefly the labors of Professor Horace L. Wells. The