Lyon, who inherited £100,000 from his father on coming of age, had a brief army career.
At the ensuing general election he came in unopposed for Seaford. At the nomination he stated his belief that
no reform was necessary. If populous towns ought to be represented, then give them the Members from those boroughs which were disfranchised for their venality and corruption, and give them also the Members for those nomination boroughs which the nominees [sic] were willing to resign. He thought that the Members who were returned for close boroughs had the interest of Birmingham, Manchester and such other towns as much at heart as any Members would have if returned for those places, because they would not be fettered by local prejudices.Suss. Advertiser, 2 May 1831.
He voted against the second reading of the reintroduced reform bill, 6 July, and for use of the 1831 census as a basis for disfranchisement, 19 July. On the proposal to disfranchise Seaford, 26 July, he cited his own success as proof that it was not ‘under nomination’; his suggestion that it be united with Hastings on the model of Sandwich and Deal was disregarded. He voted in favour of allowing the freeholders of the four sluiced boroughs to retain their votes, 2 Sept. He divided against the passage of the bill, 21 Sept., and the second reading of the revised measure, 17 Dec. 1831. His only other known vote against it was on the enfranchisement of Tower Hamlets, 28 Feb. 1832. He voted against government on the Russian-Dutch loan, 26 Jan., 12 July, and was in the minority of 16 against the Greek loan, 6 Aug. 1832.
By his own later account, Lyon ‘retired into private life, living chiefly abroad’, after the disfranchisement of Seaford.
The following summer he married, at St. Margaret’s Westminster, the actress daughter of Henry Swanborough, a failed and bankrupt accountant, who in 1861 became lessee and manager of the Strand theatre. (He cut his throat two years later in a fit of ‘temporary insanity’ and was succeeded in the management by his widow.)
On the death of his only surviving brother David in 1872 Lyon inherited his properties at Goring, Sussex and Balintore, Forfarshire, as well as his London house in South Street, Park Lane. He subsequently sold his own house in Upper Grosvenor Street. He stood for Shoreham as a Liberal at the general election of 1874, but finished a very distant third. In 1886 he moved his London home to 1 Hill Street, Berkeley Square, which cost him £5,600. He died at Goring in April 1892. By his will, dated 8 Mar. 1863 he provided his wife with an annuity of £1,400 and legacies of £5,400. He left £70,000 to his second son Fitzroy David Lyon (1862-1914) and £58,000 to his youngest son Nathaniel John Lyon (1865-1907), with an additional sum of £12,000 to be invested in a life trust fund. He was succeeded at Goring by his eldest son William Francis Lyon (1861-1925), on whose death the estate passed to Fitzroy Lyon’s daughter Joy Betty Marina.
