Skip to main content

Trinity College Dublin, The University of Dublin

Trinity Menu Trinity Search



You are here News & Events

Unveiling of commemorative plaque to John Joly, Professor of Geology and Mineralogy (1879)

September 2015

A commemorative plaque to John Joly, the Trinity scientist was unveiled on 26 September at his birthplace, Hollywood House, Bracknagh, Co. Offaly. The plaque was unveiled by Dr. Patrick Wyse Jackson, Associate Professor in Geology, who spoke on the life and significance of John Joly's scientific work.

John Joly was born in the rectory on 1st November 1857 but lived most of his life in Dublin. He was educated at Trinity College, Dublin where he remained for the whole of his career which culminated in his appointment as Professor of Geology and Mineralogy in 1897. He held this chair until his death in 1933.

Amongst his considerable scientific achievements were his invention of a colour photographic process, his studies on melting points of minerals and the specific heat of gases, his geochronological investigations into the age of the Earth for which he utilised several different schemes, and he was a pioneer in the study of radioactive elements in rocks. He was instrumental in establishing the Irish Radium Institute which advanced the medical and therapeutic uses of radioactivity.