a) The Bishop Denvir Collection. The library of Cornelius Denvir (1791-1866), a friend and supporter of Daniel O’Connell. These are mainly Mathematics and Science books; a few are of great rarity and value.
b) The O’Laverty MSS: 16 Gaelic manuscripts acquired by Monsignor James O’Laverty, historian of the Diocese of Down and Connor including catalogue compiled by Eoin McNeill.
c) The Donnellan MSS: 2 beautiful Gaelic manuscripts from the South Armagh/North Louth region.
d) The O’Laverty Historical Library. A set of books mainly comprised of Irish history, biography, archaeology and folklore.
e) The Mooney Collection: an impressive set of Bibles, Psalters , theological and philosophical works brought from the Irish College at Salamanca in the mid-19th century and presented to Bishop Dorrian.
f) Books, cuttings and fragmentary notes of Laurence O’Neill, Lord Mayor of Dublin, c 1918-1924
g) Archives of St Malachy’s College including lists of former students c1856-1926, account books c1844, school registers, 19th and 20th century roll books, some memoirs, diaries, film and photographs. There are programmes of dramatic productions, Sports Days, and Prize Givings. The diaries include The Journal of G.S. Cosslett (1794), The Diary of Edward Keyes (1914), The War Diary of Patrick Rogers; there are letters written by Padraig Pearse, Michael Collins and other historical figures.