Chaux-De-Fonds, La, a borough of Switzerland, in the canton and 9 m. N. W. of Neuf-chatel; pop. in 1870, 19,930. It is a large scattered town, resembling an assemblage of form houses and hamlets, a garden plot surrounding every cottage. It is situated in a rugged narrow valley of the Jura, at an elevation of more than 3,000 ft. above the sea. Great prosperity prevails among the inhabitants, mainly owing to the manufacture of clocks and watches, of which this place and the neighboring town of Locle are the chief seats. The number of persons employed in this manufacture in the vicinity is about 12,000, who produce annually 800,000 gold and silver watches, worth about $7,000,000. In 1774 the number produced was about 300. The manufacture is not carried on in factories, but in the separate dwellings of the workmen, each of whom usually makes only one particular piece, leaving even the finishing of it to others. The inhabitants excel also in carving, jewelry, and enamelling, and in various other arts of the same kind, and in the manufacture of chemical, mathematical, and surgical instruments, and of lace.

The painter Leopold Robert and the mechanicians Droz (father and son) were born at La Chaux-de-Fonds. There are here two subterranean mills, turned by the stream before it sinks into a deep chasm underground, the rocks having been blasted out to give space for the mills. The Doubs, which flows on the neighboring French frontier, traverses a fissure in the limestone, and a few miles N. of Chaux-de-Fonds has a fall of 80 ft., below which for nearly 6 m. it runs between cliffs 800 or 1,000 ft. high.