Biographical material, 1836-1941, relating to Dan Isaac Davies, pioneer of the teaching of Welsh in schools, including two letters, 1836-1844, of his father-in-law Jenkin Edwards (ff. 1-4); family birth, death and marriage certificates, 1850-1887 (ff. 5-17); biographical notes partly in the hand of his eldest daughter Mary Margaretta Davies (ff. 40-2); printed matter including the Cymmrodorion Society's Preliminary Report on the use of the Welsh language in elementary schools, 1884 (ff. 22-34 verso); and newspaper cuttings, 1887-1940.