Notebook of Henry Dilworth Gilpin for a course on natural philosophy at the University of Pennsylvania, ca.1819, with additional notes on mathematics. The professor for both courses was probably Robert Maskell Patterson.

A key spokesman for the medical establishment against the antivivisection movement, Walter B. Cannon was head of the Council for the Defence of Medical Research of the American Medical Association from 1908 to 1936. He and his colleague William W. Keen monitored antivivisectionist activity, mobilized the medical profession, lobbied politicians, testified in public hearings, and wrote tirelessly in defense of animal experimentation. Cannon was George Higginson Professor of Physiology at Harvard Medical School and head of its physiology department. Keen was a prominent surgeon and neurologist from Philadelphia. The Cannon Papers consist of over 1.5 linear feet of correspondence, 1905-1928, primarily between Cannon (1871-1945) and Keen (1837-1932) regarding their mutual opposition to the antivivisection movement.

Principal correspondents in the lettes of John Fries Frazer include Alexander Dallas Bache, Louis Agassiz, Joseph Henry, and Titian Ramsay Peale who discuss mainly general scientific topics, although personal and family matters are discussed with Bache. Topics include the University of Pennsylvania, boiler explosions, chemistry, education, the National Academy of Sciences, the Smithsonian Institution, fossils, magnetism, solar eclipses, the American Philosophical Society, weights and measures, the U.S. Coast and Geodetic Survey, scientific instruments, the American Civil War, electricity, the United States Mint, the Franklin Institute, scientists of the period, natural history, and publications.

Robert Maskell Patterson (1787-1854, APS 1809) was a professor of chemistry and natural philosophy at the University of Pennsylvania (1812-1828) and professor of natural philosophy at the University of Virginia (1828-1835). He was director of the U.S. Mint from 1835 to 1851. His father, Robert Patterson, was a revolutionary soldier, professor of mathematics at the University of Pennsylvania (1779-1814), and director of the U.S. Mint (1805-1824).