Sir William Parsons, 4th Bt., is listed by Thomas Mac Nevin, The History of The Volunteers of 1782 as one of the twelve Generals in the Volunteers under the Commander in Chief, The Earl of Charlemont. He, together with four others, represented King's County at the Grand National Convention held in Dungannon on 15 February 1782. Samuel Lewis, Topographical Dictionary of Ireland......with Historical and Statistical Descriptions (1838), vol. II, p. 456, notes that two meetings of delegates from several volunteer corps were held at Birr in 1781 and 1782. Sir William was also M.P. for King's County and died in 1791

For a detailed discussion on 'Volunteer' glass see Peter Francis, 'Franz Tieze (1842-1932) and the re-invention of history on glass', The Burlington Magazine, May 1994. A creamware teapot and a jug, both inscribed and dated 'Sir William Parsons and the Birr Volunteers Feb^y 27^th 1776' are in the collection of the Earl of Rosse, Birr Castle, Parsonstown, see Robert Day, Some Mementoes of the Irish Volunteers