Sir William Mayne bought Gatton off Sir George Colebrooke for £75,000, a sum that reflected the value of its parliamentary status as much as its ‘designer’ estate. He was a widower of 48 whose latest wife was 19 year old Sarah Otway: He ran the Royal Exchange Insurance Company which was one of only two corporates competing with Lloyds coffee house and had acquired estates (and an Irish parliamentary seat) in Carysford in Ireland. Surprisingly, perhaps, he had been taken with the Irish reform movement and from 1761 had tried for an English seat (Canterbury) to further its cause. He failed each time but finally won Canterbury the same year that he bought Gatton. So his brother Robert was given the Gatton seat together with William Adam, a fellow Scot (who wounded Charles Fox in a dual, over Fox having called Adam “a Beast of Nature, a Pest of Society, and a Libeller of Mankind” for his support of Lord North in 1779. They later became good friends.).
Mayne’s allegiance was bought by Lord North with lucrative victualling contracts for the West Indies & America, together with an Irish peerage (“Lord Newhaven”) in 1776. As the House of Lords no more included Irish peers than the Commons included Irish seats, Lord Newhaven remained entitled to sit for an English seat in the House of Commons. He continued to plead for Irish trade concessions and was critical of the Government’s conduct of the American war, but he voted with it to the end.
Possibly in connection with the final success of the American Revolution in 1782 the Mayne family business went bankrupt and his brother Robert committed suicide. Unfortunately Gatton’s parliamentary status was now more of an impediment than an asset and Lord Newhaven’s cousin wrote “The Gatton estate is not yet sold nor will be at the price his Lordship puts on it - £36,000. This vanity will ruin him”. In neighbouring Bletchingley the Clayton owners thought themselves lucky to sell out their interest in that borough for only £10,000. In 1785 Pitt put forward a Reform bill which would have bought out rotten boroughs, and Lord Newhaven was one of its supporters. However the bill was defeated by 248 to 174 votes. Lord Newhaven then purchased Upper Gatton and conveyed the combined estates with their dual representation capability to relatives, the Grahams of Kinross, to dispose of as they saw fit.
In 1788 Samuel Whitbread expressed an interest in the unified Gatton and was told the price was £86,000. In 1789, John earl of Caithness bought it for £80,000, realised he couldn’t afford it, and committed suicide. Later that year the Grahams succeeded in selling Gatton proper to Robert Ladbrooke for £74,000 and the Upper Gatton to Mark Currie of East Horsley – who gave one of the seats to a relative in the 1790 election.
Strong government was vital with the start of the French revolutionary wars. In 1794 Habeus Corpus had to be suspended. The economy was in desperate straights and in 1796 Ladbroke was lucky to sell Gatton to John Petrie, freshly rich from India, for £110,000, this recovery in value being a reflection of the wartime concentration of power in the Government. Support for greater democracy may have been maintained by the likes of Burke, Fox and Sheridan, but practical imperatives gave majority support to such laws as the notorious Combination Acts 1799/1800 which made workers’ groups illegal.