Meggers, William Frederick

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MEGGERS, WILLIAM FREDERICK

(b. Clintonville, Wisconsin, 13 July 1888; d. Washington, D. C., 19 November 1966)

physics.

Meggers was reared on a farm near Clintonville, Wisconsin, to which his parents, John Meggers and the former Bertha Bork, had emigrated from Pomerania in 1872. A self-made man who placed a high value on education, he supported himself while attending Ripon College (1910), largely by playing a trombone in a dance orchestra, and earned his doctorate at Johns Hopkins University (1917).

Inspired by Bohr’s classical work “On the Constitution of Atoms and Molecules,” he chose spectroscopy as his lifework. After serving as assistant in the new spectroscopy section at the U.S. Bureau of Standards, he became chief of the section in 1919, a post he held until 1958.

His achievements provide a lasting contribution to our knowledge of atomic structure. He was an expert in observing, measuring, and interpreting optical spectra. From intricate spectra he deciphered the quantum structure of many atoms and ions: energy levels, terms, quantum numbers, and configurations. He worked on some fifty spectra of about thirty elements—a unique record. His generosity in sharing his splendid line lists with co-workers was outstanding.

Meggers’ name will always be associated with standard wavelengths of light. For almost a decade he was president of the Commission of the International Astronomical Union, which was responsible for recommending international standards. The first such standards, dating from 1910, were interferometric measurements of lines observed with an iron arc as source.

He developed an electrodeless198Hg lamp, which he hoped would be accepted as the source for the primary standard of length, but it was not adopted. In 1958, however, he reported the first interferometric wavelength measurement, by using radiation emitted from an electrodeless thorium halide lamp. Some five hundred thorium wavelengths now supersede the early iron standards, with at least a tenfold increase in accuracy.

A pioneer in spectrochemistry, Meggers fully realized the value of utilizing laboratory spectra for identification and quantitative analysis of commercial substances. To this end he instituted an extensive program in which the spectra of seventy metallic elements were observed under standardized conditions, and the relative intensities of some 39,000 spectral lines were determined to provide requisite data for quantitative work.

He was an excellent photographer and was a member of the Bureau orchestra in the early days. He had valuable coin and stamp collections, which he left to the American Institute of Physics to establish a foundation for training students in science.

He served also on many important committees and received many high honors. It has been truly said that “all of these are trivial compared to the esteem and admiration of his colleagues” [P. D. Foote]. Meggers was content to spend hours at a comparator measuring wavelengths of spectral lines. From these patiently accumulated, reliable data he solved many intricate problems on atomic structure, which to him was an abundant reward for his years of painstaking effort.

His zest for knowledge took other turns. He invested heavily in many collections, ranging from buttons to light bulbs to phonographs, with the belief that they had educational value. They were housed in the “Meggers Museum of Science and Technology,” located over his garage, and he and his friends spent pleasant evenings in this museum enjoying travelogues illustrated by the splendid color slides he accumulated on his extensive travels, or listening to favorite records played on the large “Regina” music box. On 13 July 1920 Meggers married Edith (Marie) Raddant; they had two sons and a daughter.

BIBLIOGRAPHY

A complete bibliography of Meggers’ writings is included in Paul D. Foote’s biographical memoir; see Biographical Memoirs. National Academy of Sciences, 41 (1970), 319–340. His most important writings include “Measurements on the Index of Refraction of Air for Wavelengths From 2218 Å to 9000 Å in Scientific Papers of the United States Bureau of Standards, 14 (1918), 697–740, with C. G. Peters; “Solar and Terrestrial Absorption in the Sun’s Spectrum From 6500 Å to 9000 Å,” in Publications of the Allegheny Observatory, University of Pittsburgh, 6 , no. 3 (1919), 13–44; “Interference Measurements in the Spectra of Argon, Krypton, and Xenon,” in Scientific Papers of the National Bureau of Standards, 17 (1921), 193–202; “Standard Solar Wavelengths (3592–7148 Å),” in Journal of Research of the National Bureau of Standards, 1 (1928), 297–317, with K. Burns and C. C. Kiess; “Infrared Arc Spectra Photographed with Xenocyanine,” in Journal of Research of the National Bureau of Standards, 9 (1932), 309–326, with C. C. Kiess; “Term Analysis of the First Spectrum of Vanadium,” in Journal of Research of the National Bureau of Standards, 17 (1936), 125–192, with H. N. Russell; Index to the Literature on Spectrochemical Analysis 1920–1939, (Philadelphia, 1941), with B. F. Scribner; “Spectroscopy, Past, Present, and Future,” in Journal of the Optical Society of America, 36 (1946), 431–448; “Dr. W. F. Meggers, Ives Medalist for 1947,” in Journal of the Optical Society of America, 38 , no. 1 (1948), 1–6; “Zeeman Effect,” in Encyclopaedia Britannica, XXIII; “Wavelengths From Thorium-Halide Lamps,” in Journal of Research of the National Bureau of Standards, 61 , no. 2 (1958), 95–103, with Robert W. Stanley; “Table of Wavenumbers,” in National Bureau of Standards Monographs, 3 (1960), with Charles DeWitt Coleman and William R. Bozman; “Tables of Spectral-Line Intensities,” ibid., 32 (1961), with Charles H. Corliss and Bourdon F. Scribner; “Spectra Inform Us About Atoms,” in Physics Teacher, 2 , no. 7 (1964), 303–311; Key to the Welch Periodic Chart of the Atoms (Chicago, 1965); “More Wavelengths From Thorium Lamps,” in Journal of Research of the National Bureau of Standards, 69A , no. 2 (1965), 109–118, with Robert W. Stanley; “Mees Medal Ceremony,” in Journal of the Optical Society of America, 55 , no. 4 (1965), 341345; “Dr. William F. Meggers,” in Arcs and Sparks, 12 , no. 1 (1967), 3–4; and “The Second Spectrum of Ytterbium (Yb II),” in Journal of Research of the National Bureau of Standards, 71A , no. 6 (1967), 396–544, edited by Charlotte E. Moore.

Charlotte E. Moore

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