Working papers, field notes, sketches, graphs, plans, maps, drawings, calculations, lecture notes, and correspondence relating to Barnes' work on soil and water conservation in Kenya, Mauritius, Basutoland and Iran. Also, some printed material relating to soil and water conservation, and notebooks used by Barnes whilst serving with the Royal Engineers during World War I.
The collection also includes letterbooks kept by R.S.W. Barnes, Robert Ogle Barnes' father, relating to his work as a contractor for the Durban Waterworks Corporation and as a civil engineer in Natal (April 1892-June 1894). One of the letterbooks has been started by R.S.W. Barnes in South Africa (April 1925-February 1926) but includes a few later letters written by R.O. Barnes in Kenya (May 1947-July 1947).