Dated on the basis that this referred to a public meeting at the Freemasons’ Tavern on 5 July 1828 to promote the Thames Tunnel. See The Times, 7 July 1828, p.8, col.a-b.
Augustus Frederick, Duke of Sussex (1773–1843, ODNB). President of the Royal Society, 1830–1838. Marc Isambard Brunel visited him on 3 July 1828 (Institution of Civil Engineers MS Brunel Diary) when he indicated that he would attend.