A collection of manuscripts, [12 cent.]-1909, from the library of Peniarth, Merionethshire, the core of the historic collection being that of the library accumulated at Hengwrt, Merionethshire, by Robert Vaughan during the seventeenth century. The collection includes many of the most important Welsh language manuscripts, including the Black Book of Carmarthen (Peniarth MS 1), the Book of Taliesin (Peniarth MS 2), the White Book of Rhydderch (Peniarth MSS 4-5) and Brut y Tywysogion (the Chronicle of the Princes) (Peniarth MS 20), as well as important manuscripts in other languages such as the Hengwrt Chaucer (Peniarth MS 392), the Law of Hywel Dda (Peniarth MS 28), Beunans Meriasek (Peniarth MS 105) and Bede's De natura rerum (Peniarth MS 540B).

Miscellaneous letters:- W. H. Goldwyer, Bristol, to Walter Scott [aft. Sir Walter Scott], 1818 (comments on an enclosed copy of a portrait of Rob Roy), W. H. Goldwyer and [Mrs.] H. Goldwyer [from Bristol] to their son[s] Henry [and John] Goldwyer, Edinburgh, 1822 (personal, the progress of the recipients' medical studies, a Masonic display in Bristol, personal), Sibthorpe Bayly, Dublin, to Henry Goldwyer, Bristol, 1836-1844 (2) (Dr. Ashe's estate) (together with a draft reply, 1844), and Reginald Smith [from Bristol] to Henry Goldwyer, 1840 (a tribute on the recipient's resignation from the 'Commandery of the Nine Elect', greetings from the 'Sir Knights'); the autograph signature of Charles Dickens cut away from a letter; a copy by 'F. P. R.' of verses ('Hoffnung') by Frederick Heyne, with a French translation by 'My Father'; and two fragments of folios of a fourteenth century Latin manuscript and a fifteenth century English manuscript used as end-papers.