CONSTANCE, Lake of (Bodensee Costnitz), a large lake of Central Europe, on the confines of Baden, Wirtemberg, Bavaria, Austria, and Switzerland. Greatest length from Bregenz to Bodmann 44 miles; greatest breadth between Rorschach and Friederichshafen 13 miles; greatest depth 912 feet; height above the level of the sea 1280 feet. It is divided into the upper and lower lakes, the latter of which contains the fertile island of Reichenau. They are connected with each other by the channel of the Rhine, which enters the lake at Rheineck, and leaves it at Stein. The shores of the lake are flat and undulating, being more fertile than picturesque. The navigation is rendered dangerous by sudden squalls, but there is a considerable traffic in rural produce, and numerous steamboats ply between the towns on the margin of the lake. Its waters are subject to sudden risings, proceeding from some unknown subterranean agency: they abound in salmon, trout, pike, carp, &c., and are frequented by numerous species of aquatic birds. To the Romans the lake of Constance was known as the Brigantinus Lacus. Its northern shore was inhabited by the Vindelicans, the southern bank was held by the Helvetians, and the south-east by the Raetians.