(anc. Lugdunum Batavorum), a celebrated city of Holland, province of South Holland, on the Rhine, or rather on that branch of it that retains the name, 10 miles E.N.E. of the Hague, and 23 miles S.W. of Amster- dam, with both of which it is connected by railway. It is surrounded with a rampart, outside of which is a wet ditch crossed by eight bridges leading to as many gates. The River Rhine flows through the heart of the town; and, like other Dutch towns, Leyden is traversed by numerous canals which divide it into about fifty small islands communicat- ing with each other by a great number of bridges. The streets are usually long, broad, and well paved; and the houses are generally of a superior class. The Breede Straat is nearly two miles in length, and is reckoned one of the finest streets in Europe. The town-hall is a picturesque old building, founded in 1574, and containing a valuable collection of paintings. St Peter's church, built in 1315, is the largest and finest in the city, and contains among its monuments one to the celebrated physician Boerhaave. The remains of a round tower, called the Burg, stand on a slight eminence in the centre of the town, and from the walk round the top the finest view of the city and neigh- bourhood is obtained. It is said by some to have been built by Drans, though others ascribe it to Hengist about A.D. 450. Near the Burg stands the church of St Pancras, built in 1280, and containing the monument of the brave burgomaster Vanderwerff, who defended the city against the Spaniards in 1574. The University of Leyden, long one of the most distinguished seats of learning in Europe, was founded by the Prince of Orange in 1575, to reward the inhabitants for their bravery in defending the town against the Spaniards. Among its professors were Scaliger, Heinsius, Gomarus, Arminius, Boerhaave; and among its students Grotius, Descartes, Goldsmith, and Fielding. It has faculties of theology, law, medicine, science, and litera- ture; and has usually from 600 to 700 students. It has also a valuable library, botanic garden, observatory, museums, &c. (See article HOLLAND.) There are likewise many fine private libraries and museums, among which may be men- tioned the Japanese collection of Dr Siebold. The manu- factures are unimportant, but it carries on some trade in grain, butter, and cheese. Historically, Leyden is chiefly noted for the gallant and successful defence made by the inhabitants in 1574 against the Spaniards under Valdez. The siege lasted for about five months, during which the inhabitants endured the greatest suffering from famine and pestilence. Pop. (1855) 37,029.

John, a celebrated linguist, antiquary, and poet, was born on the 8th of September 1775, at Denholm, a village on the banks of the Teviot, in the parish of Cavers, and county of Roxburgh. His father was a shepherd, and was descended from a long line of farmers who had lived on the estate of Cavers. From his second to his sixteenth year, Leyden lived with his parents in a retired cottage near the foot of the "stormy Ruberslaw," where he was taught to read by his father's mother, and where his favourite books were the Metrical Histories of Bruce and Wallace, the Poems of Sir David Lindsay, the Arabian Nights' Entertainments, and Paradise Lost. He learned writing, arithmetic, and the elements of Latin grammar, during a short attendance of three years at the school of Kirtstown; and after studying Latin and Greek for two years under Mr Duncan, a Cameronian minister at Denholm, he entered the University of Edinburgh in November 1790. There, though his knowledge was at first very inaccurate, and the language in which he expressed his ideas so awkward as to set his fellow-students in a roar, he soon became noted for his attainments, not only in the prescribed studies, but in French, Spanish, Italian, German, and the ancient Icelandic. The vacations were generally passed in his native wilds amongst his own relations, with the exception of the summer of 1792, when he acted as assistant, with little success, in a school at Whitebanklee or Clovenfords, a village on the skirts of Ettrick Forest. At this time his appearance was very prepossessing. He was ruddy and fair, with a frame rather delicate than robust, and an expression of great good nature and gentleness in his features.

In November 1793 he began the study of divinity, but at the same time devoted much of his attention to historical research, to philology, to metaphysical speculations, and to natural history and medicine. He was a member of various debating societies, in all of which he distinguished himself by the fluency and copiousness of his unpremeditated harangues, rather than by any graceful or polished eloquence. In one of these institutions, he contracted an intimacy with Henry (now Lord) Brougham, and with Dr Thomas Brown and Francis Horner. About the same time he formed an acquaintance with Dr Robert Anderson, editor of the British Poets, and Thomas Campbell.

When he had completed his theological education, he accompanied the two sons of Campbell of Fairfield to St Andrews in 1797, where he attended the lectures of Dr Hunter, professor of humanity, and of Principal Hill, one of the divinity professors. He also entered the Theological Society, and was soon considered the best speaker, among such members as Professor Duncan of St Andrews, Lord Campbell, and Dr Chalmers. From the presbytery of St Andrews he received license to preach in May 1798; and returning to Edinburgh he preached frequently, but without attracting any popular admiration.

In the winter of 1798 he attended some of the medical classes, and at this period inflicted a lasting injury on his health, and nearly lost his life, by his rash and unskilful treatment of a complaint which he believed to be an attack of colic, but which proved to be enteritis. In addition to his duties as resident tutor in the family of Mr Campbell, he had been engaged as a writer in the New London Review; and, amongst other articles, contributed those on Horne Tooke's Diversions of Purley, on Dr Thomas Brown's Observations on Zoonomia, and on Vallancey's Sanscrit History of Ireland.

In the summer of 1799 he published A Historical and Philosophical Sketch of the Discoveries and Settlements of the Europeans in Northern and Western Africa, at the close of the Eighteenth Century. This interesting work, although written in about six weeks, whilst the author was in bad health, and at a distance from books, exhibits proofs of extensive information and sound reflection. An enlarged edition of it was published in 1817 by Mr H. Murray.

Through Mr Richard Heber, to whom he was introduced by Mr Constable, he became acquainted with the most distinguished literary characters in Edinburgh, and, amongst others, with Sir Walter Scott, whom he greatly assisted at this time in editing the Minstrelsy of the Scottish Border, by recovering old ballads from oral tradition, and by communicating spirited imitations of the ancient bards, and valuable materials for the notes.

In 1800 a plan formed to establish him as assistant and successor to the minister of his native parish, failed, in consequence of the reluctance of the incumbent to agree to it. Soon afterwards, an attempt which he made to obtain the professorship of rhetoric and belles-lettres in Edinburgh, was also frustrated.

About this time he made two successive tours through the Highlands, and collected much curious information, which was never published. He wrote several poems, founded on the remains of Celtic story, one of which, the beautiful ballad of The Mermaid, has been inserted in the Border Minstrelsy. In 1801 he contributed to Lewis's Tales of Wonder, and published an edition of The Complaint of Scotland.

In 1802 he contributed many articles to the Scots Magazine, of which he had been newly appointed editor. He was also employed in collecting the papers of the Highland Society for publication; and he edited a volume entitled, Scottish Descriptive Poems, with some Illustrations of Scottish Literary Antiquities. Early in this year he offered to the African Society to explore the interior of that continent, in which so many Europeans have perished. His friends, alarmed at this, became eager to obtain for him an Indian appointment; and, through the interest of Mr William Dundas, he was nominated assistant-surgeon in the Company's service, on condition that he should take a surgical degree. After intense study for six months, he received the necessary diploma. The degree of Doctor of Physic was conferred upon him by the University of St Andrews, on the 7th August 1802. Meanwhile, he had finished his longest poem, Scenes of Infancy.

Leyden, after spending the winter in London, sailed from Portsmouth on the 7th of April 1803, and soon after his arrival at Madras, was attached as surgeon and naturalist to the commission for surveying the districts of the Mysore. In this latter capacity he was expected to turn his attention, not only to the natural history of the country, but to the manners, institutions, and language of the inhabitants. His labours hurting his constitution, obliged him to remove to Prince of Wales Island. Here he was befriended by the governor, Mr Dundas, and here, too, he procured the chief materials of the Essay on the Languages and Literature of the Indo-Chinese Nations, contained in the 10th volume of the Asiatic Researches.

He removed in 1806 from Prince of Wales Island to Calcutta, where, through the favour of the governor-general, Lord Minto, he was appointed one of the professors in the Bengal College, but was soon transferred to the office of Judge of the Twenty-four Pergunnahs of Calcutta. In 1809 he was appointed a Commissioner of the Court of Requests in Calcutta; and, in the end of the following year, having resigned this office, he obtained the office of Assay Master of the Mint. Soon afterwards, he accompanied Lord Minto upon the expedition to Java, for the purpose of collecting information touching the learning and institutions of the native tribes, and assisting the governor-general in negotiating with the local authorities, and in adjusting the future government of the country. After the British troops took possession of the city of Batavia, he caught fever from having ventured rashly into an ill-shed library, supposed to contain many Indian manuscripts, and died on the 21st of August 1811, after an illness of three days.

Shortly after Leyden's death, Lord Minto and Sir John Malcolm both publicly expressed their high estimation of his extensive erudition, his unwearied pursuit after knowledge, and his exemption from all sordid vices. A few personal foibles, such as his egotism and awkward deportment, did not render him less endearing to his friends. His Poetical Remains were published in 1819, with a memoir by the Rev. James Morton; and in 1826 appeared his posthumous work, entitled Memoirs of the Emperor Baber. An Essay on the Life of Leyden is contained in Scott's Miscellaneous Works.