A collection consisting of :
- A letter book, 1893-1907 in which most letters are addressed to Mr Lockwood who represented the interests of the Chubut Railway in Buenos Ayres. Their content reflects the problems faced by the Welsh immigrants - the threat of Indians, the unstable economy, floods etc.
- Two account books of E. J. Williams as surveyor in the construction of canals etc. in Patagonia, 1891-1896, 1902-1903.
- Papers relating to the departure of E. J. Williams from Patagonia in the summer of 1907 - his farewell speech, a programme of the farewell concert, letters and poems, a Spanish petition and report regarding the extension of the railway to the Andes, a report on San Antonio and a history of the life of Lewis Jones.
- Also relating to Patagonia, there is a detailed plan of the Chubut Colony, 1885 with the names of every landowner. Also, a map of west Argentina with a route of a journey highlighted.
- A plan of the sections and seams and strata proved in the River Dee Coalfield near Mostyn, 1876.
- An essay in Welsh entitled A Geology Handbook submitted to the 1879 Birkenhead Eisteddfod.