A collection of approximately 5,000 volumes that originally formed part of the collections from St Benedict's Abbey, Fort Augustus, deposited in the National Library in 1992. The Cassidy books were not the property of the Trustees of St Benedict's Abbey but had been placed there for safe keeping. On the dissolution of St Benedict's Abbey the Cassidy books were transferred into the custodianship of the English Benedictine Congregation Trust and are now on deposit in the National Library as a separate collection. A selection of the other books from St Benedict's Abbey was purchased by the Library: for this, and the Abbey's history, see Fort Augustus (St Benedict's Abbey) Collection. The Cassidy Collection was brought together in the 1830s-1860s by an Irish Franciscan, the Rev. Thomas Cassidy, whose book label and/or signature serves to identify books belonging to the collection. It is said that many of these books were purchased from book stalls on the quays at Dublin. There are nine incunabula and many rare books from the 16th, 17th and 18th centuries.