This series is arranged alphabetically and contains biographical material, writings, correspondence, and subject files pertaining to the professional career of William Weldon Watson. "Bibliography and biographical sketch" and "Genealogical notes" provide information on Watson's publications, life, and family background. "Comments on Onsager's Research on Thermal Diffusion in Gases" and "Physics at Yale, 1928-1968" are hand-written documents composed by Watson after his retirement from the Yale faculty in 1968. "Writings" provide a sampling of Watson's publications written throughout his professional career.