George Charles Keidel (1868-1942) was associate professor of Romance Languages at Johns Hopkins University and was later a librarian at the Library of Congress. The collection spans the years 1899-1935 and consists largely of Prefessor Keidel's lectures and writings on romance paleography. Some material is in French.

Robert Larimore Pendleton (1890-1957) was a soil scientist and professor of geography at Johns Hopkins University. The collection consists of two bound reports: "Soils and Land Use in Peninsular Siam," by Pendleton, and Pendleton's copy of "Soil Series Bibliography," by Charles F. Shaw and Mark Baldwin. The reports span 1938-1949.

The collection consists of approximately 230, loose photographs and photostats of title pages used as plates in the published volume: Seventeenth Century Maryland: A Bibliography published in 1949.