Parsons, Laurence

Laurence Parsons, Fourth Earl of Rosse (1840-1918)

Both the 72 inch and the smaller 36 inch telescopes at Birr were rather unwieldy and had no mechanism to drive them. Laurence Parsons, Fourth Earl of Rosse, tackled this problem and invented mechanisms for the purpose. However, it is essentially for measuring the heat of the moon that the Fourth Earl is best known. He built an instrument on which the 36 inch telescope could focus the lunar radiation and produced temperature graphs whose accuracy were only recognised long after his death.

During his life he received many distinctions, including an LL,D and a D.Sc. from the University of Dublin, where he served as Chancellor. He was also President of the Royal Dublin Society.