Manuscripts collected by Gwilym Cowlyd, mainly consisting of material relating to Ieuan Glan Geirionydd. Includes account book of the father of Ieuan Glan Geirionydd, 1813-1817; the poetical works of Ieuan Glan Geirionydd, Gwilym Cowlyd and Dafydd Jones of Trefriw (Dewi Fardd). Also a book of sermons on various subjects, described as the property of John Mostyn, curate of Denbigh and William Chambers, curate of Bodfari in 1795 (the hand is that of John Williams, bellringer of Tremeirchion in 1792).
Manuscripts relating to Capel y Beirdd in Eifionydd. Notebooks of W. Davies, 1815, Owen Davies, 1828 and Owen Roberts, 1841. Also accounts of Capel y Beirdd from 1849-1855.
Manuscripts relating to the Baptists. A notebook belonging to Rev. Thomas Evans, Baptist minister at Llanrwst and Llanddoged, Denbighshire. Notebook of Richard Williams, Llantrisant, Anglesey, details of subscriptions towards the registration of the Baptist Chapel in Caernarfon to conduct weddings, 1876; also two account books of Pontllyfni Baptist Chapel, 1884, 1887-1891.
Manuscript of Rev. John Jones, Tal-y-sarn. Notes on sermon topics.