Papers and photographs, 1888-1924, 1972, mostly manuscript letters by Simpson-Baikie to his wife, Marion Evelyn Simpson-Baikie, Lady Simpson-Baikie, 1906-1919, including letters whilst on active service on the Western Front, Gallipoli, Salonika and Palestine, 1914-1918; four manuscript letters from Simpson-Baikie to his mother-in-law, Emilita Miller, 1904-1918, and three manuscript letters from Simpson-Baikie to his daughter, Jean Simpson-Baikie, 1917-1918. Also, manuscript letter from Gen Sir Ian Standish Monteith Hamilton to Jean Miller Hamilton, Lady Hamilton, asking her to inform Marion Evelyn Simpson-Baikie that Simpson-Baikie has been chosen to serve at Gallipoli, 1915; manuscript letter to Simpson-Baikie from Gen Sir Horace Lockwood Smith-Dorrien, Governor of Gibraltar, on adverse comments about Smith-Dorrien in 1914 (Spiers, London, 1919) by FM John Denton Pinkstone French, 1st Viscount of Ypres, 1920. Eleven photographs and two negatives relating to Simpson-Baikie's career, 1888-1920, including three photographs of Simpson-Baikie, 1888, [1904]; Lt Gen Horatio Herbert Kitchener, 1st Baron Kitchener of Khartoum, General Officer Commanding in Chief, South Africa, with his Aide de Camp, Lt Francis Aylmer Maxwell [1901]; Maj Gen Hubert Ion Wetherall Hamilton, Maj Gen General Staff, Mediterranean Command, 1911; Gen Sir Ian Standish Monteith Hamilton at Charing Cross station, London, on his departure for Gallipoli, 13 Mar 1915; aerial photograph of the French camp at Sedd el Bahr, Gallipoli, Turkey, 1915. Typescript letter to Jean Morley Kennerley (née Simpson-Baikie) from Professor Robert Clifford Walton concerning Smith-Dorrien, 1972.

Papers and photographs, 1913-1958, including fourteen panoramic photographs produced by Survey Company, Royal Engineers, Salonika Force, labelled to show topographical details, Feb 1917; 'Salonika fire', 18-19 Aug 1917, a series of 24 official photographs of the city, taken by Survey Company, Royal Engineers and Royal Flying Corps; two photographs, one of a uniformed group including Stevenson, [1946], and the other of an unidentified painting showing construction work on an airfield [1940]. Papers relating to the evacuation of Royal Engineers establishments in Beit-Nabala and Haifa, Palestine, 1948. Editions of Notes on building materials and their uses (School of Military Engineering, Chatham, 1913); 'RMA (Royal Military Academy) Magazine', Vol XV, No 58, Nov 1914.