(b. Boston, Massachusetts, 5 August 1843; d.Cambridge, Massachusetts, 18 February 1923)
Trowbridge was a pioneer in the movement that established serious scientific research in America in the latter decades of the 19th century. The son of a prominent New England family, John Trowbridge studied at the Boston Latin School and graduated in 1865 with highest honors from the Lawrence Scientific School of Harvard University. After five years of teaching, he became professor of physics at Harvard (1870), serving in this capacity for forty years until his retirement in 1910.
Trowbridge was a strong advocate of laboratory practice as an integral part of scientific education. To this end he formally urged, as early as 1877–1878, the endowment of a “building devoted to physical investigation,” with a staff dedicated to scientific research. He pointed out that while “there are no precedents for the endowment of a Physical Laboratory in connection with an American University, there is the greater honor in becoming the leaders”. He then designed and carried out the construction at Harvard of the Jefferson Physical Laboratory. He served as titular head upon its completion in 1884 and as director from 1888 until his retirement.
Trowbridge’s main line of research was concerned with electrical phenomena. He devised the cosine galvanometer (1871) to measure strong electrical currents. With W. C. Sabine in 1890 he investigated high-frequency electrical oscillations using a revolving mirror. As early as 1890 Trowbridge supported the view that the carriers of electricity in wires were something other than atoms. By 1894 he investigated the magnetic effect of high-frequency oscillations and was one of the many pioneers of remote signaling. In 1895 he investigated with Duane the velocity of propagation of electrical waves. He undertook studies of the discharge of electricity through gases and, from 1896, examined both the production and effect of Röntgen radiation. In 1897 he studied with Theodore W. Richards the spectrum of argon and other gases. Aware of the need for a constant source of high voltage, he developed, also in 1897, a storage battery of 10,000 cells. In addition to his scientific work he was the associate editor of the American Journal of Science from 1880 to 1920.
I. Original Works. Trowbridge published over one hundred original papers and several books dealing with scientific subjects. His most important book is What is Electricity? (London, 1897). A partial bibliography is included in Edwin H. Hall, “John Trowbridge: 1843–1923,” in Biographical Memoirs. National Academy of Sciences, 14 (1930), 185–204, which also includes a discussion of some of the papers. This list is supplemented by the Royal Society Catalogue of Scientific Papers, XIX, 214–215.
Trowbridge wrote “Recent Advance in Physical Science,” in International Monthly, 1 (1900), 123–132; and “Progress of Electricity From 1800 to 1900,” in The Nineteenth Century: A Review of Progress (New York-London), 417–427. His “The Endowment of the Physical Laboratory at Harvard College” (Cambridge, Mass., ca. 1877), in the Harvard University Archives, HUF 693.77.24, includes a bibliography of the published research under the direction of Trowbridge between 1871 and 1877 in support of his proposal. He also described the endowment and construction of the laboratory in “The Jefferson Physical Laboratory,” in Science, 5 (1885), 229–231.
Trowbridge’s correspondence is in the Harvard College Library and in the Harvard University Archives.
II. Secondary Literature. Edwin H. Hall contributed the article on Trowbridge for the Dictionary of American Biography. Theodore Lyman wrote the biographical article “John Trowbridge 1843–1923,” in Proceedings of the American Academy of Arts and Sciences, 60 (1925), 651–654. Further biographical literature is cited in Max Armin, ed., International Personal-bibliographie, II , 687. The work of Trowbridge on remote signaling is considered by E. Hawks in Pioneers of Wireless (London, 1927), 121–128.
Thaddeus J. Trenn