Professional papers of Ywain Goronwy ap Griffith comprising agreements, specifications, plans and correspondence, 1927-53, mainly relating to the alteration, repair and erection of new buildings, both private and public, in Merionethshire, Montgomeryshire and Caernarfonshire; files relating to work done in the diocese of Bangor, mainly in the form of alterations and repairs to vicarages, 1932-1952; and papers, 1920-40, relating to the redemption of tithe rent-charges in various parishes of Anglesey, Caernarfonshire, Cardiganshire and Merionethshire.