Dumbartonshire, a Scottish county, 25 miles long and 1 1/4 to 15 1/2 miles broad, with an area of 270 sq. m., of which 30 belong to a detached south-eastern portion. Loch Lomond (22 by 5 miles) lies on the eastern boundary, and sends off the Leven 7 miles to the Clyde; the southern is washed by the Clyde's broadening estuary; and the western, for 17 miles by its offshoot, Loch Long, which forms with the Gare Loch (7 miles by 7 furlongs) the wooded Rosneath peninsula. The surface, almost everywhere hilly or mountainous, culminates in Ben Vorlich (3092 feet); and the scenery, with its sea-lochs, lake, woods, and glens, is lovely as that of few regions in Scotland. Coal is mined in the detached portion, which nowhere exceeds 480 feet above sea-level. The climate is mild and humid. Barely a fourth of the entire area is in tillage; but many sheep and cattle are reared. Colquhoun of Luss is much the largest proprietor. Rosneath Castle is a seat of the Duke of Argyll. Since 1728 bleach and print fields, dyeing and cotton works, have multiplied in the Vale of Leven; shipbuilding is an important industry. The chief towns are Dumbarton, Helensburgh, Kirkintilloch (in the detached portion), Alexandria, Renton, and Bon-hill. Dumbartonshire returns one member. Anciently part of the Levenach or Lennox, it retains some vestiges of Antoninus' Wall, and has memories of St Patrick, Bruce, Rob Roy, Smollett, and Henry Bell. Pop. (1801) 20,710; (1881) 75,333; (1901) 113,865. See works by J. Irving (1860-79) and Sir W. Fraser (1860-74).