The local Indexes show another reference to Barkla related material (check the Indexes for more details): letters to Barkla from Professor Sir D. F. Tovey (1875-1940) mainly about meetings of the Faculty of Music, Edinburgh University, 1918-1938, at Gen. 1971/5/1-3, 5-15. In addition, the UK National Register of Archives (NRA), updated by the Historical Manuscripts Commission, notes: correspondence and papers, Private, NRA 22850 Barkla; letters to Sir Owen Richardson, University of Texas at Austin, Harry Ransom Humanities Research Center Library, NRA 22337 Richardson; letters (10) to Lord Rutherford, 1909-1921, Cambridge University Library, Department of Manuscripts and University Archives, Ref. Add 7653.