Douglas, William, 1st Duke of Queensberry (1637 -1695)
William Douglas, 3rd Earl of Queensberry, was the eldest son of James, 2nd Earl, and his second wife, Margaret, daughter of John Stewart, 1st Earl of Traquair. He succeeded his father in 1671, was sworn of the Privy Council of Scotland in 1677, appointed Lord Justice General of Scotland in 1681, made Marquess of Queensberry, hereditary Lord High Treasurer for Scotland, and Governor of Edinburgh Castle in 1682, and Duke of Queensberry in 1684. In 1682 he was granted the right to add the double tressure flory counterflory to his arms. He married, in 1657, Isabel, daughter of William Douglas, 1st Marquess of Douglas. His library was sold at auction by John Ballantyne in Edinburgh 18 November 1813. He presented the library of his second son Lord George Douglas, who died in 1693, to the Advocates Library in Edinburgh, and these books are marked with the same three stamps. The books from his own library can be easily recognized from the form of their shelfmarks. Lord George's books usually have a donor's inscription.