Student notebooks and experimental notebooks. The student notebooks (1899-1905) consist of lecture and laboratory notes taken by Davis while a student at Columbia University, the University of Gt̲tingen, and Cambridge University's Cavendish Laboratory. Courses and professors at Columbia University include Mechanics, taught by Robert S. Woodward; Light Theory, by William Hallock; and Electronics and Magnetism, by Michael I. Pupin. At the University of Gt̲tingen courses included Mechanics, taught by R.G. Weber; Basic Mechanics and Magnetism, taught by Woldemar Voigt; and Electric Phenomena, by Carl V.E. Reicke, as well as other courses (teachers unidentified) on thermodynamics, the theory of gases, and electric phenomena in gases. At the Cavendish Laboratory courses included Electrodynamics, taught by Sir Joseph Larmor, and Hydrodynamics by Sir George Stokes. The experimental notebooks (1899-1900) are for work done while a research fellow at Columbia University in the fields of electricity and magnetism, electron dynamics, and circuit equations.