Two notebooks containing a description by 'Watkin ap Mair Gwilym' of a system of arithmetic based on the dozen with a new terminology in Welsh, and exercises in arithmetic.

Three volumes of Latin and arithmetic exercise books of Walter Cecil Davies, son of Walter Davies.

A volume compiled by David Evans ('Dewi Glan Llugwy'), Llanrwst, containing weather lore entitled 'Hen Draddodiadau Dywediadau a Diarebion yr hen Bobl ynghylch y tywydd &c yn yr Oesoedd gynt Wedi eu Casglu ynghyd o lyfrau a hen ysgrifau a chan hen Bobl ...'; extracts from 'Llyfr Meddygon Myddfai'; 'Wyth Ran Dyn a'u hanian'; a collection of old traditions ('Casgliad o Hen Draddodiadau') of interest to Edeyrnion, Llandrillo-yn-Rhos, Mochdre, Castell Dinas Bran, etc., and tales and traditions entitled 'Siarad o Bulpud', 'Syr Watcyn ar Gwyddelod', 'Llyn Tegid', 'Pont ap Hywel [Pontypool]', and 'Gwrecsam'; rules of multiplication ('Rheol Lluosogiad') taken from a manuscript in the parish of Llanelian, Denbighshire; and 'Hirhoedledd', being an account of the descendants of a long-lived couple in Tregaron, 1874.

An incomplete transcript made by John Jones, Gellilyvdy, of a treatise on arithmetic. It is entitled 'Llyfr Sion ap William ap Sion o Gyfrifyddiaeth'.

A commonplace book belonging to Rowland Eames, Penrhyndeudraeth, 1776-1781, and containing notes on arithmetic, accounts, recipes, 'cerddi' and 'carolau', hymns, precedents of legal documents, music, night-school memoranda, a highway account for Llanfrothen, 1790, etc.

Notes on 'Foundation sacrifices', 'Influence of gambling upon arithmetic', etc.

A volume containing rent accounts of Messrs. Jones & Parry with individual tenants [? in North-East Wales], 1817-1827, and the original manuscript of Richard Hughes: Rhifyddeg Gymraeg a Saesoneg . . . Welsh and English Arithmetic . . . (Llanrwst, 1832).