Page:Popular Science Monthly Volume 72.djvu/287

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award of the Nobel prize and the Copley medal to Dr. A. A. Michelson, professor of physics in the University of Chicago, is of interest to Americans from more view points than one. Naturally and properly, it gratifies their national pride. But more than this, it marks a widespread recognition of the development of pure science which has recently occurred in this country, and the partial attainment of those ideals advocated so vigorously by Rowland in his "Plea for Pure Science," addressed to the American Association for the Advancement of Science at its Minneapolis meeting. In the past these ideals have been typified by the work of Franklin, Henry, Gibbs and Rowland—honorable names—but separated by intervals all too long.

But most important of all is the encouragement which pure science is now receiving from various sources. For while all prizes and research funds combined can do little to kindle or encourage the spirit of investigation in the mature mind, they do elevate the position of the investigator-and foster the ideals of pure science in such a way as to make a career of research more attractive to able and ambitious youth. Great things may be hoped for American science when once the trend of young talent has set less exclusively to commerce and engineering.

In the history of optics Professor Michelson's work is certain to form a large chapter. His highly accurate determination of the speed of light is already a classic. His interferometer, devised for the purpose of detecting relative motion between earth and ether, bids fair to become the standard richly earned instrument for the measurement of all minute distances. Few facts in contemporary science are, indeed, more striking than the quiet and modest, but effective, manner in which Michelson and Benoit have, by their determination of the standard meter in terms of the red cadmium wave-length, morally, though not legally, established the wave-length of light as the international standard of length.

Another means for dealing with quantities in the sixth and seventh decimal places is Michelson's echelon grating which is perhaps the most powerful spectroscopic device now available. The product of his new engine for ruling diffraction gratings is awaited with great interest especially by astrophysicists.

The superficial observer may be tempted to identify the work of Michelson with the accurate determination of certain numerical constants. A greater mistake could not be made. For in nearly every case these determinations have been made possible by the discovery of some important method or principle whose fruitfulness it is impossible as yet to estimate.

For forty years after its enunciation the principle of Avogadro remained practically unrecognized by chemists. Nor is this tardiness in the recognition of scientific values confined to scientific men. Faraday had both the dynamo and the electric motor in full operation in 1831; but these machines were not placed on the market until about 1876. We therefore attempt no accurate estimate of the achievements of Professor Michelson, but merely extend to him the congratulations which he has so