# History of the Department

Physics was a required course at Harvard College by 1642. At that time, the text was by Aristotle.

In 1726, Thomas Hollis of London endowed a professorship in "Mathematicks and Experimental Philosophy" and also donated a shipment of scientific apparatus. In 1738 the second occupant of the Hollis chair, John Winthrop, introduced his students to Newton's Principia, although, from a surviving manuscript, it is not clear whether he completely grasped Newton's Laws. Still, he made history as one of the first American observers of astronomical phenomena, such as the transits of Venus.

Count Rumford (originally Benjamin Thompson of Woburn, Massachusetts), who is said to have bootlegged physics courses at Harvard when still a poor boy, became one of the discoverers of the Law of Conservation of Energy, and left the endowment for the Rumford Professorship in 1814.

### Jefferson Physical Laboratory*

The Jefferson Physical Laboratory was born under the ascending star of experimental inquiry, as reflected in triumphant 19th-century terms by Pasteur.

As is so often the case, the whole enterprise was realized when the dream of an academic met with the encouragement of an administrator and the support of philanthropists. The Laboratory opened its doors in 1884; it is the oldest of its kind in the United States, designed specifically for physics research as well as for instruction.

This innovation had its own unexpected history. When President Charles W. Eliot took office in 1869, he espoused a relatively new view - that liberal education should contain science and modern languages in addition to the classics and theology. At the time, laboratory science was taught almost exclusively at special scientific and technical schools, of which Harvard's Lawrence Scientific School (1847), Yale's Sheffield Scientific School (1847), and the Massachusetts Institute of Technology (1865) were early examples. But Eliot's vision did not yet include research: "The prime business of American professors in this generation must be regular and assiduous class teaching." Harvard's only professor of physics at the time, Joseph Lovering, offered no challenge to Eliot on that score. As remarked by Edwin H. Hall, it was doubtful that he "ever made an original experiment, or any experiment not required for his lectures."

All this changed when John Trowbridge joined the faculty in 1870 as assistant professor of physics. A graduate of the Lawrence Scientific School, he brought with him the recognition of the importance of laboratory research to the future of physics. He did not mince his words: "The department of physics in a University must embrace both teaching and investigation. If it is given up entirely to teaching, the cause of science suffers, and the object of a University which is founded both to teach and increase the sum of human knowledge is defeated." (1877)

Perhaps his shrewdest move was his publication in 1879 of a collaborative paper surveying the laboratory apparatus in the United States - which revealed the newly established Johns Hopkins University owned almost seven times as much physical apparatus as did Harvard.

By 1880, Eliot had come to agree with Trowbridge's idea - then strange in America - that physics instruction should not be by rote and from books, but in the laboratory, "with objects and instruments in hand"; and, moreover, that physics instruction required immersion in research as well. Planning could now begin for a new building for both purposes. An anonymous "friend of the University" came forward to give $115,000 on condition that another$75,000 would be raised to cover the running costs of the facility. The anonymous donor turned out to be the Boston businessman Thomas Jefferson Coolidge (class of 1850). The name of the building honors Coolidge's ancestor, the President who was both a supporter of and occasional contributor to science in America.

By 1883, the additional money had been raised, primarily through the generosity of Alexander Agassiz. When the building opened in the fall of 1884, its very design and "plainest possible" furnishings - down to the unpainted inside brick walls - were statements opposing the ornate European style of laboratory construction. All facilities for teaching undergraduates were kept to the east wing, to minimize vibrations in the west wing owing to "disturbances incidental to the movement of large numbers of persons."

In order to further minimize disturbances and noise from the street traffic, 300 ft. away, the central tower in the research wing was built on a separate foundation. The tower's walls, not linked to the rest of the structure, would serve to support delicate measuring instruments. All ferromagnetic materials were to be eliminated from the fixtures, pipes, and furnishings in the west wing. Thus it was hoped that the magnetic field of the earth - whose variation was a lively research topic of the day - would pervade the building unchanged.

Not everything worked as planned, and since this made research on geomagnetism less interesting, that was perhaps all to the good. The red bricks themselves turned out to be slightly magnetic, somebody had forgotten about the ferromagnetic steampipes, and the marshy ground beneath the tower proved an unsteady support. But the splendid space, the fine shop for the design and construction of apparatus, and the tradition of precision measurement prepared for the meeting of research challenges that had not even been anticipated.

Within two decades of its opening, the Laboratory and the Department had developed to the point at which Trowbridge could boast that Harvard now had "the best equipment of any Physics Laboratory, either in this country or abroad."

### Early Figures in the Life of Jefferson Laboratory

###### Edwin H. Hall(1855-1938)

Joseph Lovering was director of the Laboratory until his retirement in 1888. He was responsible for buying most of the apparatus during this period, but his first love remained experimental demonstrations for classroom purposes.

John Trowbridge, the guiding force behind the design of the Laboratory, was the first of the modern men in physics at Harvard. Despite heavy teaching and administrative duties, he published over 80 research papers, with the best known work on spectroanalysis and Röntgen rays. For that purpose, he designed and had constructed a storage battery consisting of 10,000 cells - giving a far larger potential difference than any other such battery at the time, and attracting research visitors far and wide.

At the time of the founding of the Laboratory, Wolcott Gibbs, a chemist, taught a course on thermodynamics for the Physics Department - although the class chiefly met in his private chemical lab in the Lawrence Scientific School nearby. Gibbs' research interests included work on complex inorganic acids, analytic methods, and physiological chemistry.

Benjamin O. Peirce, a Harvard undergraduate, was Trowbridge's first research student. His brilliance became evident early. Of a research paper on magnetism, it was said "There was not... in all America at that time another college Junior capable of all this." He taught both physics and mathematics, and the bulk of his research dealt with electrostatic and magnetic measurements.

Edwin H. Hall joined the faculty in 1881, having completed his PhD at Johns Hopkins University and discovered the effect which bears his name. At Harvard he turned to research on thermoconductivity, thermodynamic behavior of liquids, and thermoelectricity. Hoping to improve physics education in secondary schools, he published a pamphlet in 1887 that established a national standard of preparation and admission-level competence for several decades.

Harold Whiting, the youngest member of the Department in 1884, was said to have an agility of mind and inventiveness approaching genius. He and his whole family perished in a shipwreck in 1895. In accord with his will, the Whiting Fellowships were established that have been supporting graduate students in the Department ever since.

Wallace C. Sabine, like Pierce a graduate student of Trowbridge (from 1886), might also count as one of the early discoveries made in the Jefferson building. He was made Instructor in 1890, and charged in 1895 by President Eliot to improve the acoustics in a lecture room of the newly built Fogg Art Museum. The result was the founding of a new science. In Edwin Hall's words: "Sabine's development of architectural acoustics, from a condition of gross and ineffectual empiricism to the status of a reasoned and fairly exact science, is probably the most notable single achievement in the history of the Jefferson Physical Laboratory during its first three decades."

By about 1910, it had become clear that Trowbridge's vision was being achieved and exceeded. In addition to Sabine, the physics faculty contained such men as George Washington Pierce, Theodore Lyman, and Percy Bridgman. All were products of the Jefferson Laboratory, where they had done their graduate work.

The physicist as both teacher and superb researcher - a curious and novel idea when Trowbridge had proposed it for the endorsement of Eliot and Coolidge - had indeed become a reality by the early part of the 20th century. Soon, new facilities were to be added to the Laboratory, and as physics came of age in America, the faculty grew larger than Trowbridge could have imagined. And the rooms, too, would be put to ever changing use, with the stream of results from them continuing to alter the direction of physics itself.

*Jefferson Laboratory History was written by Gerald Holton, with assistance from Deborah J. Coon, Armand Dionne and the Harvard University Archives.