The John O’Donovan series mainly comprises letters addressed to John O’Donovan but also includes letters to third parties that were forwarded to O’Donovan and draft letters and notes written by O’Donovan. The subjects discussed in the letters reflect O’Donovan’s work and personal interests and are broadly related to the following – Ordnance Survey correspondence, genealogical research, manuscript research and publishing, topographical queries and archaeology and antiquities.

The series contains letters from over 380 individuals many of whom were well-known antiquarians and historians of the period.

The Rev. James Graves series consists mainly of correspondence addressed to Graves, predominantly on antiquarian and archaeological matters, e.g.:

  • Articles to be published in the Journal of the Kilkenny Archaeological Society.
  • Reports of archaeological finds and sketches of artefacts from fellow antiquarians and enthusiasts.
  • Discussions on historical sources especially concerning Kilkenny (e.g. Statutes of Kilkenny or St. Canice’s Cathedral).

The Rev. Charles Graves series contains documents relating to the business of the Brehon Law Commission make up the bulk of this series, including:

  • Bound minute books and draft minutes.
  • Draft and printed reports submitted to Parliament.
  • Copies of official correspondence with officials in the Irish administration.
  • Lists of recipients of complementary copies of publications.
  • An inventory of the documents in the series created by T. W. Lyster in 1884.

A large number of transcripts and translations of Brehon Law tracts, mainly in the hand of O’Donovan and O’Curry.

The series also contains incoming correspondence addressed mainly to Graves frequently referring to delays which caused difficulties for the project. It also includes correspondence to Graves on the subject of Endowed Schools and Ogham studies.