The collection is comprised of artefacts, plans and drawings of the Clashawaun Works (jute spinning mill) and its machinery. The business records include; material relating to the formation of the limited company in 1888; correspondence with directors and partners; notices of meetings and resolutions adopted; some handwritten minutes and material relating to the formation of the limited company to a public company in 1937.

Letter from Dalkeith Holmes Plunkett-Johnston at Bolart, Clara, King's County (County Offaly), to Maria Blanche Fuller at Bayview Lodge, Salthill, County Galway, regarding a pair of gloves he sent her, and his lost riding coat.

Three letters from Dalkeith Holmes Plunkett-Johnston at Bolart, Clara, King's County (County Offaly), to Maria Blanche Fuller at Bayview Lodge, Salthill, County Galway.

Five envelopes containing miscellaneous estate accounts and financial and estate correspondence of the Birr Estate Office, much of it about arterial drainage (including printed matter back to 1869), one account of 1874 mentioning the cost of labour on the mounting for the three-foot telescope, and other long runs of accounts relating to the Dovegrove, Killeen and Newtown farms and stock, and to the manor saw mill, 1886-1912. [Not in chronological order.]

Letter from Edward H Armstrong, Secretary of The Armstrong Clan at Kirkton, Dumfries, Scotland, to Canon Adam Lamb at Woodfield, Clara, County Offaly, Ireland, regarding two recently discovered continuations of 'History' by John Armstrong.

Correspondence and maps concerning Lisheen military rifle range, beside the 4th Earl’s property at Clonoghill, on the outskirts of Birr.

Letter from Eva Sophia Marsh at Woodfield, Clara, County Offaly, to her sister Maria Blanche Plunkett-Johnston.

Letter from Charlotte Jane Johnston at 39 Waterloo Road, Ranelagh, County Dublin, to her granddaughter Constance Plunkett-Johnston. The letter is kept in an envelope addressed to Constance Lamb at Tinamuck, Clara, King's County (County Offaly), from 8 August 1911.

Two letters from Abraham Augustus Fuller at Woodfiled House, to his niece Constance Lamb at Slade House, Penhill Road, Cardiff. He congratulates her on her second pregnancy, and mentions his visit to Mount Jerome Cemetery, a conversation with Major George Gamble, and Cleonice Gamble's upcomming wedding.

Letter from Francis William Lamb at 24 Leeson Park, Dublin, County Dublin, to his wife Constance Lamb, regarding Woodfield House. Includes a photograph of three women, two children, and a dog seated in a doorway.