The papers consist of three volumes, being collections of poetry in the hand of Peter Bailey Williams, Rector of Llanrug and Llanberis, Caernarfonshire from 1792 until 1836. The first volume is dated 1794. They contain the works of Aneirin, Taliesin, Guto'r Glyn, William Llyn, Gruffudd Grug and numerous other Welsh poets.
Also included are two volumes, once owned by Griffith Williams, Gutyn Peris, 1769 - 1838. The first volume is a collection of poetry in various metres in the hand of the aforementioned, together with his autobiography. The second volume contains the rules of Welsh poetry.Also included is a volume of Festival Sermons written in a late seventeenth century hand and preached at various London Churches between 1690 and 1706.
Amongst the manuscripts of Gwynedd himself, there are poems, addresses, Eisteddfod compositions and Eisteddfod adjudications. Also, a collection of diaries, 1880-1921. In addition, the collection includes a group of correspondence addressed to Gwynedd and copies of replies written by him,1890-1923, mostly relating to Eisteddfod matters. There are extracts from the Aber Vestry Minute Book, 1820-1894, a list of the members of the Gorsedd of the Bards, 1911 and a journal of a visit to the United States in 1889 which records some interesting impressions of Washington, Buffalo, Boston, Oneida, Utica and other towns en route.