(b. Richmond, Ohio. 4 June 1859; (d. Evanston, Illinois, 17 February 1953).
physics, astrophysics. education.
Crew was descended from devout Quaker farmers and merchants in Jefferson County, Ohio. His father, William Henry Crew, who ran a successful general store, died when Henry was eleven, providing in his will for his son and two daughters to receive a “classical education.” Henry’s mother. Deborah Ann Hargrave Crew, devoted herself to the children’s upbringing; and it was more from her than from the local school that he learned to read and write. His first physics lessons came from activities like harnessing horses, winnowing wheat, preserving fruit, and visiting the gunsmith’s shop or the sawmill. Crew’s heritage gave him good health and a vigorous interest in the world around him along with intelligence and mechanicalingenuity. A career in research, however, also needed opportunities, which were in short supply at the time. In his old age Crew noted that “I have made no contribution to knowledge which is of either first-rate or secondrate importance.” Nevertheless, among other honors he became president of the American Physical Society in 1909–1910. of the American Association of University Professors in 1929, and of the History of Science Society in 1930.
His education was so backward that Crew was two years older than most of his classmates when he entered high school in Wilmington, Ohio, and when he went to Princeton in 1878. Following his father’s wishes, he assiduously studied Latin, Greek, and mathematics, although as a boy he had already found them dull and irksome. What did excite him were concrete subjects such as geology and botany: he enjoyed camping and fishing. collected thousands of fossils during the summers, and analyzed flowers and vegetables in the garden he kept.
In his junior year at Princeton. Crew took a physics course using the then-standard textbook of Ganot, translated from the French. Thenext year came laboratory work and, particularly inspiring, a course in general astronomy under Charles A. Young. On graduation Crew won a fellowship in physics and stayed on, but, as he later wrote, “In the absence of any regular graduate course in physics, I browsed in the library, played in the laboratory, and deteriorated intellectually,” In the fall of 1883 he therefore went to study in Europe.
At Hermann von Helmholtz’s laboratory in Berlin, Crew met other American students, who told him about the graduate school that Henry Rowland had created at the Johns Hopkins University in Baltimore. Crew went there in the spring of 1884 and became an assistant to Rowland, helping with measurements of the solar spectrum and certain physical constants. In 1887 he received his Ph.D. for a dissertation that used Doppler spectroscopy to determine the rotation period of the sun at various heliocentric latitudes; it was a hard task with the limited optical equipment at hand, and Crew later learned that his measurements were without value.
From 1888 to 1891 Crew was instructor in physics and then department head at Haverford College, Along with his teaching duties he developed a cleverway to make a constant-temperature bath. This was not a route that could lead far, and in 1891—shortly after he married Helen C. Coale of Baltimore—he accepted an invitation to go to Lick Observatory.
At Lick, Crew found a tiny, isolated group of astronomers irreconcilably split by a struggle between two factions. He took the first chance to leave that appeared, becoming professor of physics at North-western University in the fall of 1892. At Lick he had measured some stellar spectra and had devised aningenious way around a problem of laboratory spectroscopy: when an are was struck to study metals, the tips tended to oxidize or weld together, Crew solved the problem by replacing one of the tips with a spinning disk.
Such a combination of telescope and laboratory studies was characteristic of a new field, astrophysics, promoted especially by George Ellery Hale. Crew served through 1941 as an associate editor of Hale’s Astrophysical Journal. But Evanston was not one of the few places with enough people and instruments to form an astrophysical research community. As the years passed, Crew attended less and less to spectroscopy and more to pedagogy.
A friendly and conscientious teacher, Crew prepared lectures and demonstrations that could be exciting without sacrifice of precision. He was especially concerned to show the connectedness of physics, the way its branches dovetailed. In 1899 he published a textbook, The Elements of Physics, which went through a number of printings and revisions and was joined in 1908 by the more advanced General Physics, which also found wide use. These texts were more approachable than Ganot’s, skipping many details of instrumentation and algebraic manipulation while retaining the key ideas. Like all textbook authors of the time. Crew hesitated to introduce new theory, although in the 1927 revision of General Physics (the fourth and last) he added a simple introduction to the Bohr atom and touched on relativity.
Crew taught physics not as an abstraction but as a concrete human achievement, and here he found history useful. In 1914 he and Alfonso de Salvio published a translation of Galileo’s Dialogues Concerning Two New Sciences that was frequently reprinted. In 1919 Crew began to give lectures on the history of science; in 1928 he published The Rise of Modern Physics, covering much the same ground as his textbooks but in a historical mode. As a historian he called himself an amateur, for here too his main interest was pedagogical.
As a teacher Crew reached his summit when he took a leave of absence from 1930 to 1933 to become chief of the Division of Basic Sciences at the Century of Progress International Exposition in Chicago. He was in charge of the Hall of Science, a central attraction of the fair, and also organized symposia, popular books, and so forth. Many of the exhibits he inspired later found a more permanent home in the Museum of Science and Industry in Chicago.
After his retirement from Northwestern in 1933, Crew remained vigorous for many years. Besides his two daughters he had a son, William Henry Crew, who also was a physicist, as was a grandson, Henry Crew III.
I. Original Works. In 1935 Crew deposited a tenpage personal history in the Archives of the National Academy of Sciences. His papers are in the Archives of Northwestern University. Evanston, Illinois, with a microfilm copy at the Niels Bohr Library of the American Institute of Physics in New York City. Among his books are The Elements of Physics (New York, 1899): General Physics (New York, 1908): The Principles of Mechanics (New York, 1908); a translation, with Alfonso de Salvio, of Galileo’s Dialogues Concerning Two New Sciences (New York, 1914; repr 1933, 1939, 1946, 1952); The Rise of Modern Physics (Baltimore, 1928; 2nd ed., 1935); and his translation of Maurolycus’s Photismi de lumine (New York, 1940).
II. Secondary Literature. Obituaries include A. A. Knowlton, “Henry Crew,” in Isis, 45 (1954), 169–174; and William F. Meggers, “Henry Crew,” in Biographical Memoirs. National Academy of Sciences, 37 (1964), 33–54. with bibliography.
Spencer R. Weart