The library of the Dalrymple family was formed largely by Sir David Dalrymple (1726-92), Lord Hailes, who added to the collection of his grandfather, Sir David Dalrymple (c. 1665-1721). Together with the manuscripts also acquired from Newhailes House, it is the most important contemporary collection to survive from the period of the Scottish Enlightenment. Although it has not survived intact - a Sotheby's sale on 24 and 25 May 1937 sold 453 lots from the library, including 23 incunables, 182 STC (see p. 3) items and many 18th-century foreign books - the collection admirably reflects the interests and achievements of Lord Hailes, a central figure in 18th-century Scottish history. The collection consists of c. 7,000 volumes and a number of pamphlets, broadsheets, prints, maps and music; British and foreign works, of the 16th to the 18th century, with three incunables and some 19th century material; and a number of examples of fine bindings and typography. It is strongest in history and biography (c. 1,800 vols.), classical and modern literature (c. 2,500 vols.), law, politics and economics (c. 1,000 vols.), and theology (c. 750 vols.); but it is surprisingly less well represented in philosophy, science and geography, despite Lord Hailes's association with contemporary philosophers and the position of his brother Alexander (1737-1808) as the first hydrographer to the Admiralty and writer on geographical matters. Notable items include Sanson's Geographie of 1696, and the four-volume Blaeu Nouveau Theatre d'Italie of 1704; a 1675 edition of vol. 1 of John Ogilby's Britannia, and the rare Ode on a Distant Prospect of Eton College (1747), Thomas Gray's first publication; splendid architectural folios include the Venice, 1616 edition of Palladio, and Perrault's Les Dix Livres d'Architecture de Vitruve (Paris, 1684). The collection is particularly strong in 17th century French history books, containing first editions of important authors such as Sully and d'Aubigne. Among the papers is the manuscript of Lord Hailes's Annals of Scotland, annotated by Samuel Johnson, and letters of his contemporaries including Hume, Robertson, Beattie and Burke. There is also a complete set in 20 bindings of Alexander Dalrymple's private and East India Company charts, published between 1769-1786, which are held in the Map Library. These were sent by Alexander to the family home in 1786 and are accompanied by the books of his East Indies nautical memoirs. The collection was accepted by the Government from the Trustees of Sir Mark Dalrymple, Bt (1915-71), in lieu of estate duty, and allocated to the National Library in 1978.
The manuscripts are described in vol. XVII (unpublished) of the Library's Catalogue of Manuscripts --- R.L. Betteridge, 'The Library of the Dalrymples of Newhailes', The Journal of the Edinburgh Bibliographical Society, 8 (2013), 33-71.