Diary, 3 Jan-5 Nov 1915, with preceding entries for 30 Oct-18 Nov 1912. [Inserted at 30 Aug 1915 letters from L.F. Perkin, 22 Jun and J.C.R. Ewing, 6 Aug and at 9 Dec a letter from J.E. Shukle, 10 Sep].
Diary, Nov 1915-Sep 1916 [Inserted at 29 Mar 1916 letters from N. Noel,? Mar and 15 Apr at 11 May 1916 telegram Laftore Rudra; at 5 Jun 1916 letter from W.Y. Lurusi, 1 May].
Diary, 19 Oct 1918-22 Aug 1936 [fragmentary for 1920-25]; with notes on the Lindsay Commission 1931 and miscellaneous notes for 1931 and 1932; also small 'Silent Messenger' pamphlet entitled The Drift of the Times. Sound the Alarm! The Spiritual Poison of the Y.M.C.A. (Kansas City).
Fragmentary diary including cuttings and annotated circular concerning lecture series organised by the French Delegation in Nagpur in which Datta took part.