The manuscripts of father William Mitchell and daughter Maria Mitchell are not easily separated, and are treated here together. The collection includes William Mitchell's autobiography, his memoir of Judge Walter Folger of Nantucket, astronomical and meteorological observations, lectures, family and other correspondence.

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).