[154] Mr., afterwards Sir Andrew Mitchell, was only son of the Rev. William Mitchell, minister of the High Church, Edinburgh, and who had the singular distinction of being five times Moderator of the General Assembly. After following legal pursuits at Edinburgh, Mr. Mitchell was in 1741 appointed secretary to the Marquis of Tweeddale, minister for the affairs of Scotland, and in 1747 was chosen M.P. for the Banff district of burghs. In 1751 he was sent as ambassador to Brussels, and in 1753 was created a Knight of the Bath and envoy extraordinary to the court of Prussia. He was a great favourite with Frederick the Great, whom he accompanied in his campaigns. He died at Berlin, on the 28th January, 1771. Boswell became acquainted with Sir Andrew Mitchell during his Continental tour. (See _supra_, pp. 43-47.) [155] Archibald, third Duke of Argyll, was born in June, 1682. As colonel of the 36th regiment he served under the Duke of Marlborough. Devoting himself to civil affairs, he was in 1705 nominated Lord High Treasurer of Scotland; in the following year he became a commissioner on the Union, and in 1710 was appointed Justice General. He was wounded at the battle of Sheriffmuir in 1715, when he held a command under his brother, the Duke of Argyll and Greenwich. He succeeded his brother as Duke of Argyll in 1743, and died 15th April, 1761. He founded the family residence at Inverary, and there established a valuable library. He was a zealous promoter of learning, and excelled in conversation. [156] The celebrated George, tenth Earl Marischal, whom Boswell had the honour of accompanying through Germany and Switzerland in 1763. Born about 1693, Lord Marischal held a high command in the army of Queen Anne, and on her death signed the proclamation of George I. Deprived of office by the Duke of Argyll, he joined the Earl of Mar in the insurrection of 1715, and at the battle of Sheriffmuir commanded two squadrons of cavalry. In 1719 he made a second attempt on behalf of the Chevalier. In the rising of 1715 he took no part. Having by a residence in Prussia gained the favour of Frederick the Great, he became Prussian ambassador at the courts of France and Spain. In 1759 he revealed to Mr. Pitt, afterwards Earl of Chatham, the family compact of the house of Bourbon; he was, consequently, invited to the court of George II., and his attainder was reversed. On possessing himself of his forfeited estates he purposed to reside in Scotland, but on the urgent entreaty of the Prussian monarch he returned to Berlin. He died, unmarried, at Potsdam, on the 28th of May, 1778. [157] Sir Adam Fergusson, Bart., of Kilkerran, LL.D., was elected M.P. for Ayrshire in 1774; he afterwards sat for the city of Edinburgh. He died 23rd September, 1813, at an advanced age.