Documentary sources for Irish art are widely scattered and vulnerable. The art library of the Royal Hibernian Academy of Arts was destroyed by bombardment during the Rising of 1916 against British rule. The absence of degree courses in art history delayed the development of art libraries until the 1960s when art history degrees were established at University College Dublin, and Trinity College Dublin. In the 1970s the state founded the Regional Technical Colleges all over Ireland with their art and design courses. Modern approaches to art education had transformed the education of artists and designers with a new emphasis on concept rather than skill acquisition. This led to theoretical teaching and the growth of art sections in the college libraries. Well qualified graduates and staff led the way in the universities and colleges to a greater emphasis on research. Archive centres of documentation on Irish art opened at the National Gallery of Ireland, Trinity College and the Irish Architectural Archive. At NCAD the National Irish Visual Arts Archive (NIVAL) became the main depository for documentation on 20th century Irish art and design. Many other libraries exist with holdings of relevance to the history of Irish art, notably the National Library of Ireland, the Royal Irish Academy, the Royal Dublin Society, the Royal Society of Antiquaries of Ireland and the National Archives.