As the scheme took shape in July Camden was to resign, and thus make possible a shifting of offices, which was to result in the Marquis Wellesley succeeding Castlereagh as secretary for war. At last, on September 6, the duke informed Canning of his own intention to retire on the ground of ill-health, and at the same time disclosed the fact that no steps had been taken to prepare Castlereagh for the proposed change in his position. Thereupon Canning promptly sent in his own resignation, the duke resigned the same day, and Castlereagh, learning what had passed, followed his example two days later.[39] Believing that Canning had been intriguing against him behind his back, under the guise of friendship, he demanded satisfaction on the 19th, and on the 21st[40] the duel was fought, in which Canning received a slight wound. Such events provoked little censure in those days, and it is pleasant to know that Canning and Castlereagh afterwards acted cordially together as colleagues. Their enmity broke up the government. The Duke of Portland did not long survive his withdrawal from office, and died on October 29; Leveson-Gower insisted on following Canning into retirement. Perceval was entrusted with the task of forming an administration, but the new ministry was not formed without considerable negotiation. Canning vainly endeavoured to impress first on his colleagues and then on the king his own pretensions to the highest office, while attempts, to which the king gave a reluctant assent, had been made to enlist the co-operation of Grenville and Howick, who succeeded his father as Earl Grey, in 1807, but they failed as all later attempts were destined to fail. The most influential motive governing their conduct was, doubtless, their feeling that they would not as ministers possess the king's confidence. Sidmouth's following had also been approached. Sidmouth himself was considered too obnoxious to some of Pitt's followers to be a safe member of the new cabinet, but Vansittart was offered the chancellorship of the exchequer and Bragge, who had taken the additional surname of Bathurst, the office of secretary at war. They refused, however, to enter the ministry, unless accompanied by Sidmouth himself.