(the Cassoromagus and Belloraei of antiquity), an arrondissement, department of Oise, in France, containing twelve cantons and 234 communes. Area 756 square miles. Pop. (in 1851) 101,983. The chief city, of the same name, is in a beautiful situation on the river Thérain, 21 miles N.W. of Paris. Pop. 12,508, employed in woollen, flax, cotton, earthenware, and carpet manufactures. The cathedral of Beauvais is one of the largest in France.

BEAVER, or CASTOR, an amphibious quadruped of the order Rodentia, with a thick glossy fur, and horizontally flattened tail, abounding in North America and Siberia, and still found in the north of Europe. It formerly appears to have been known as far south as the Rhone and the Danube; and though with us now extinct, was formerly an inhabitant of Great Britain. The fur of the beaver forms a considerable article of commerce. Among traders the skins are distinguished into three kinds: 1. The fresh beaver, which is obtained in winter, before the animal has shed any of its hair, and consequently that is most esteemed by furriers. 2. The dry or lean beaver, which is captured in summer, when the animal is moulting. 3. The fat beaver, which differs from the fresh only in having acquired additional softness and oiliness from being worn for some time on the persons of the native hunters. This is the kind that is chiefly used in hat-making. The substance called castor is found in pouches in the inguinal region of the beaver. It is regarded as a powerful antispasmodic. See MAMMALLIA.

BEAVEN, that part of a helmet which covers the face.