The collection consists mainly of correspondence regarding the death of R. Silyn Roberts and the sale of his books, the Workers Educational Association, Bethel Chapel in Tanygrisiau, Merionethshire, the death of the brother of Mary Silyn Roberts in Australia and other matters. Also, there are letters written by Mary Silyn Roberts and R. Silyn Roberts to Professor F. Rnning, Copenhagen, Denmark, 1904-1922.
There are lectures and general notebooks which belonged to Mary Silyn Roberts when studying at the University College of Aberystwyth, pre 1905; reports and letters regarding the Women's Land Army in Wales, 1914-1918; a photograph of the grave of R. Silyn Roberts and a ticket of a meeting at Mynydd y Cilgwyn Chapel, 1846.