The collection consists of Francis Pease's research papers. It contains correspondence, manuscripts, Pease's notes (including his work notes, many of which contain various drawings and diagrams by him), reprints, photographs, etc. Topics covered in the collection are numerous and include the Mount Wilson Observatory, the Yerkes Observatory, astronomy and astronomers. The majority of it relates to Pease's research on the speed-of-light (highlighting his manuscript with Albert A. Michelson), Ether drift, his observations of the Moon, the Sun, Jupiter, star diameters, galaxies, nebulae, as well as his work on interferometers, and the design and construction of telescopes. Participants in the collection include: Giorgio Abetti, Walter S. Adams, Robert Grant Aitken, Edward E. Barnard, Paul Brockett, Clifford Crump, Arthur L. Day, George Ellery Hale, Albert A. Michelson, Robert A. Millikan, George Moffitt, Frank E. Ross, Henry N. Russell, Harlow Shapley, J. Vaurie, Latimer J. Wilson, F. E. Wright, William Hammond Wright, American Society of Mechanical Engineers, Carnegie Institution of Washington, Corning Glass Works, Crucible Steel Company of America, National Research Council (U.S.), Scientific American, inc., Southern California Edison Company, and Spencer Lens Company. There are reprints of articles by Thomas C. Chamberlin, Ejnar Hertzsprung, Sir James Hopwood Jeans, and J. C. Kapteyn.