Research into Sir Isaac Newton (1642-1727) Letters to De Beer regarding his research into Isaac Newton, particularly into the validity of the falling apple story. De Beer enquires about cuttings of the tree which were supposedly taken and replanted at Lord Brownlow's residence at Belton. Also included are typescript copies from Sir Steven Tallents' file on Newton. Copies of De Beer's outgoing letters are interspersed throughout. Jul 1950-May 1955