Letter from J.T. Warburton to Roger Casement voicing his dissatisfaction at how the whole episode involving him has been disgracefully "mismangaed by the headquarter committee" and has negatively affected the public perception of the Irish Volunteers in England, 1914 Jun. 11.

Postcard from J.T. Warburton to Roger Casement saying that he has accepted the offer "to come over and drill and organise the National Volunteers", 1914 Jun. 3.

Letter from J.T. Warburton to Roger Casement outlining his credentials as an officer and expressing his wish to join the Irish Volunteers, 1914 Jun. 2.

Letter from F.T. Warburton, Clapham, to John Devoy regarding his letters to the 'Gaelic American', the First World War, John Redmond and his suggestion that Clan na Gael funds should be used to start Ireland's "peat-fuel industry", 1914 Aug. 13.

Letter from J.T. Warburton to Roger Casement saying that the decision of his committee has put him in a difficult position as he had taken Casement's proposal for an offer, 1914 Jun. 6.

Letter from J.T. Warburton to Roger Casement about the setting up of a London Irish Brigade and other military matters, 1914 Jun. 1.

Mr. Richard Warburton, of Garryhinch, and his tenants. :

Protest against rack rents in Queen's County. (Repr. from the Leinster Leader of March 19, 1881).

Letter from J.T. Warburton to Roger Casement saying that he could "give much valuable assistance in the Volunteer movement if I could afford the expense", 1914 Apr. 20.

Letters to John Redmond, 1902 Aug. - Nov.

Letter from Colonel F.T. Warburton, Concanon Road, to George Gavan Duffy hoping to arrange a meeting with Roger Casement, 1916 May 22.

Letter from F.T. Warburton, Brixton, to George Gavan Duffy regarding the trial of Roger Casement, 1916 Jun. 6.

Letter from F.T. Warburton to John Devoy regarding John Redmond, the Irish Parliamentary Party and the Ancient Order of Hibernians, and suggesting that Ireland stops using British coal, 1913 Mar. 26.

Letter from F. T. Warburton to George Noble Plunkett, Count Plunkett, enclosing a letter from Laurence Warburton and mentioning the peat industry, with a copy of enclosed letter, 1917 June 21.

Letter from J.T. Warburton to Roger Casement which alludes to being asked "to undertake the task of ascertaining the best and cheapest rifle" and other matters relating to drills, 1914 Jun. 7.

Letter from J.T. Warburton to Roger Casement asking him to try and get "$25,000 for one local peat manufactory, as an object lesson" , 1914 Aug. 12.

Letter from J.T. Warburton to Roger Casement in which he talks about the current state of the Irish Volunteers and how he initially advocated "a return to the volunteer movement of 1782", 1914 Jun. 24.

Letter from J.T. Warburton to Roger Casement in which he points out the flaws in adopting the English drill and explains how changes should be made as well as including diagrams as a further outline, 1914 Jun. 25.

Letter from F.T. Warburton, Lieutenant Colonel, Royal Engineers, Retired List, to George Gavan Duffy regarding Roger Casement's defence in his trial, 1916 May 14.

Letter from J.T. Warburton to Roger Casement about drills and the Irish Volunteers, 1914 Jun. 19.

Letter from J.T. Warburton to Roger Casement in which he discusses Ulster, John Remond and the Home Rule bill, 1914 Jun. 3.