Of the Thornton brothers, ‘all City people and connected with merchants, and nothing but merchants on every side’, Henry was the most obvious heir to his father’s evangelical and philanthropic endeavours. Inheriting £40,000 from him in 1790, in addition to his partnership in the London bank of Down, Thornton and Free and a share in the family business interests at Hull, he devoted six-sevenths of his income to charity until his marriage in 1796 (when he was worth £7,000 p.a.) and one-third thereafter. A sharp critic of his father’s rough and ready approach to life, he aspired to the suaviter in modo of his cousin William Wilberforce who described him in 1789 as ‘a most excellent, upright, pure, and generous young man: may it please God long to continue him a blessing to the public, and to amend his health’. Wilberforce saved him from ‘a sort of infidelity’ and set up house with him from 1792 until his marriage; their enthusiasm for the abolition of the slave trade secured him the chairmanship of the Sierra Leone Company founded in July 1791 to promote African commerce and civilization. He had championed the Company in the House that session and by the end of the year it kept him busy ‘from morning till night’, so that ‘at present, business, politics, friendship, seem all suspended for the sake of it’. He informed the House, 2 Apr. 1792, that he was proud to be the only merchant supporting abolition of the slave trade that day. Around him and Wilberforce gathered the Clapham Sect, or the ‘Saints’ as they were dubbed, including Charles Grant I and Edward James Eliot. The King remarked that he hated ‘such canting Methodists’ as Thornton.
On his unopposed election in 1790, Thornton had combined the profession of ‘just support to administration’ with his perennial claim to independence of party: ‘he never gave one party vote’. He favoured relief for religious dissenters, and abstained from voting with Pitt on the Russian armament; and on 30 Dec. 1794, 26 Jan., 6 Feb. and 27 May 1795 joined Wilberforce in voting on principle for a negotiated peace with France. He admitted (26 Jan.) that the moment was not propitious and, having presented a petition from Southwark in favour of peace on 6 Feb., scrupulously presented a counter-petition on 20 Feb. He was satisfied that the majority of his constituents were in favour of legislation against sedition, 1 Dec. 1795, and next day signed the London merchants’ declaration of support for Pitt. At his re-election in 1796, when he headed the poll, he was still a ‘general friend of administration’, having at first supported the war with France and then waived his objections to it on discovering that government could not honourably negotiate peace. He was prepared to support a temperate and seasonable reform of Parliament and voted for it, 26 May 1797. That session he was a respected spokesman before the secret committee on the Bank of England and a member of the finance committee; he then investigated the Ordnance accounts and, in the following session, the victualling office. He claimed his constituents’ pressure for his opposition to Pitt’s triple tax assessment, 14 and 18 Dec. 1797, but apart from a proposal to improve commercial assessment, he approved the income tax as the only way to continue war finance, 27 Dec. 1798, and silently raised his own contribution in accordance with the proposal he had made in the House. In 1798 and 1799 he assisted Wilberforce by promoting a bill to limit the African slave trade, which was eventually defeated in the Lords, 5 July 1799. He was a champion of paper money, 27 Nov., 5 Dec. 1800, 23 Mar. 1801, denying that it adversely affected the price of provisions, and in 1802 published his views in an authoritative Enquiry into the nature and effects of the paper credit of Great Britain.
Thornton welcomed the purity of the Southwark election of 1802, in which he again headed the poll; he had complained in the House, 20 Feb. 1797, of the abuses prevalent under a system of electoral treating. He admitted that he had gone far in supporting government and was well disposed to Addington, who had made peace with France.
Thornton tried to interest the Portland ministry, too, in taking over the Sierra Leone Company, 29 July 1807, and in the following year succeeded. After the abolition of the slave trade, a jubilant Wilberforce had asked him ‘well, Henry, what shall we abolish next?’ The reply was, ‘The lottery I think’. In fact it was economical reform that preoccupied Thornton in the Parliament of 1807.
No place or pension ere he got
For self or for connection
We shall not tax the Treasury
By Thornton’s re-election
was the verse sung by his Southwark supporters.
On 31 Jan. 1810, having seconded Bankes’s motion to abolish offices in reversion in perpetuity, he was renamed to the finance committee. He had voted with ministers on the address, 23 Jan., but joined opposition throughout on the Scheldt inquiry, so that they listed him ‘hopeful’. He supported Bankes’s amendment to the army estimates, 1 Mar. He voted against Burdett’s imprisonment and for the release of Gale Jones, 5, 16 Apr., and on 15 June presented his constituents’ petition for Burdett’s release. He voted for Romilly’s bid to limit the imposition of capital punishment for theft, 1 May, spoke and voted for sinecure reform, 3 and 17 May, and voted for parliamentary reform, 21 May 1810: he was circularized, unavailingly it seems, by the Friends of Constitutional Reform in 1811. He joined opposition on the Regency questions of 1 and 21 Jan. 1811 and voted for the election treating bill, 25 Mar. He opposed the reinstatement of the Duke of York as commander-in-chief of the army, 6 June. That session he spoke as a member of two committees: that on commercial credit, appointed 1 Mar., supporting their findings, and as a member (sometimes chairman) of the bullion committee appointed the previous session.
Thornton, with Francis Horner and William Huskisson, had prepared the report of the bullion committee which he defended on 6 May 1811. He set out to prove that if the shortage of specie had its origin in an unfavourable balance of trade, it was exacerbated by the quantity of paper money in circulation, which must be restricted. These views he further defended against his critics on 13 May and published. He went on to express reservations about the bank-note bill, 15 July 1811, 26 Mar., 10 Apr. 1812, but admitted, 8 Dec. 1812, that the time was not ripe for the resumption of cash payments by the Bank, which led Robert Peel to suppose that he had made a ‘complete recantation’. He could scarcely have concurred.
Thornton was listed ‘doubtful’ by the Treasury after his re-election in 1812. As if to confirm this, he opposed Vansittart not only on his bank-note bill but also on his plan of finance, which damaged the sinking fund, 3 Mar., 25 Mar., 7 Apr. 1813. He supported Catholic relief throughout the session and defended the sinecure regulation bill, 29 Mar. He gave a qualified support to the East India Company commercial monopoly, 3 June, suggesting that it be extended, for the time being, to free London merchants. Like his two brothers in the House, he held East India Company stock. He supported Christian missions in India, one of his own interests, and was an advocate (like his father) of relief of prisoners for debt, 8 Apr., and of a resident clergy, 8 July. His attendance fell with declining health in 1814, when he voted for Romilly’s bill against attaintment, 25 Apr.; supported the election expenses bill, 9 May, the London prisons bill, 14 June, and the relief grant to German war victims, 14 July. He had been added to the select committee on the corn trade on 7 Apr. 1813; a year later he advocated the postponement of measures for agricultural protection, 6 May, and was named to the new select committee of 6 June. He died 16 Jan. 1815, an outstanding philanthropist, the intellectual mainstay of the Clapham evangelical group and a most scrupulous Member of Parliament.