Laurence Parsons, 4th Earl of Rosse, Baron of Oxmantown, 7th Baronet of Birr Castle, was born 17 November 1840 to William Parsons, 3rd Earl of Rosse, and Mary Field. Like his father, he pursued astronomy and is known for his attempt to design a truly flat mirror to use in a telescope. Lord Rosse succeeded his father as the 4th Earl of Rosse in 1867. In the same year he was elected a Fellow of the Royal Society. From the year of 1867-68, Lord Rosse served as a Justice of the Peace for King’s County, and was appointed High Sheriff of King’s County. On 1 September 1870, he married Lady Frances Cassandra Hawke, daughter of Lord Edward Harvey-Hawke, 4th Baron of Hawke, and Lady Frances Fetherstonhaugh. From 1881-87 Lord Rosse was the Vice-President of the Royal Society. From 1885 to 1908 he serves as the 18th Chancellor of Trinity College, Dublin. He also was the Lord Lieutenant of King’s County, and Custos Rotulorum of King’s County from 1892 until 1908. In 1896 he was elected President of the Royal Irish Academy. In 1902 he received the honorary degree of Legum Doctor from the University of Wales, sharing the ceremony of the instalment of the Prince of Wales as Chancellor of the University of Wales. The 4th Earl of Rosse died on 29 August 1908, and was succeeded by his son, William Parsons, 5th Earl of Rosse.