chief ministers included Robert Walpole, Lord Townshend (Walpole's brother-in-law), Lord Stanhope and Lord Sunderland. In 1717 Townshend was dismissed, and Walpole resigned from the Cabinet over disagreements with their colleagues; Stanhope became supreme in foreign affairs, and Sunderland the same in domestic matters. Lord Sunderland's power began to wane in 1719. He introduced a Peerage Bill that attempted to limit the size of the House of Lords by restricting new creations. The measure would have solidified Sunderland's control of the House by preventing the creation of opposition peers, but it was defeated after Walpole led the opposition to the bill by delivering what was considered "the most brilliant speech of his career". Walpole and Townshend were reappointed as ministers the following year and a new, supposedly unified, Whig government formed. Greater problems arose over financial speculation and the management of the national debt. Certain government bonds could not be redeemed without the consent of the bondholder and had been issued when interest rates were high; consequently each bond represented a long-term drain on public finances, as bonds were hardly ever redeemed. In 1719, the South Sea Company proposed to take over £31 million (three fifths) of the British national debt by exchanging government securities for stock in the company. The Company bribed Lord Sunderland, George's mistress Melusine von der Schulenburg, and Lord Stanhope's cousin, Secretary of the Treasury Charles Stanhope, to support their plan. The Company enticed bondholders to convert their high-interest, irredeemable bonds to low-interest, easily tradeable stocks by offering apparently preferential financial gains. Company prices rose rapidly; the shares had cost £128 on 1 January 1720, but were valued at £500 when the conversion scheme opened in May. On 24 June the price reached a peak of £1,050. The company's success led to the speculative flotation of other companies, some of a bogus nature, and the Government, in an attempt to suppress these schemes and with the support of the Company, passed the Bubble Act. With the rise in the market now halted, uncontrolled selling began in August, which caused the stock to plummet to £150 by the end of September. Many individuals—including aristocrats—lost vast sums and some were completely ruined. George, who had been in Hanover since June, returned to London in November—sooner than he wanted or was usual—at the request of the ministry. The economic crisis, known as the South Sea Bubble, made George and his