See _Corpus Inscriptionum Latinarum_, i. No. 195; Polybius i. 22; Diod. Sic. xvii. 44; Frontinus, _Strat._ ii. 3; Florus ii. 2; Cicero, _De senectute_, 13; Silius Italicus vi. 667; and PUNIC WARS.
DUISBURG, a town of Germany in the kingdom of Prussia, 15 m. by rail N. from Düsseldorf, between the Rhine and the Ruhr, with which rivers it communicates by a canal. It is an important railway centre. Pop. (1885) 47,519; (1900) 92,729; (1905), including many outlying townships then recently incorporated, 191,551. It has six Roman Catholic and six Protestant churches, among the latter the fine Gothic Salvatorkirche, of the 15th century. It is well furnished with schools, which include a school of machinery. Of modern erections, the concert hall, the law courts and a memorial fountain to the cartographer Gerhard Kremer (Mercator) are worthy of mention. There are important foundries, rolling mills for copper, steel and brass plates, chemical works, saw-milling, shipbuilding, tobacco, cotton, sugar, soap and other manufactures.
Duisburg was known to the Romans as _Castrum Deutonis_, and mentioned under the Frankish kings as _Dispargum_. In the 12th century it attained the rank of an imperial free town, but on being mortgaged in 1290 to Cleves it lost its privileges. At the beginning of the 17th century it was transferred to Brandenburg, and during the Thirty Years' War was alternately occupied by the Spaniards and the Dutch. In 1655 the elector Frederick William of Brandenburg founded here a Protestant university, which flourished until 1802.
DUK-DUK, a secret society of New Britain or New Pomerania, Bismarck Archipelago, in the South Pacific. The society has religious and political as well as social objects. It represents a rough sort of law and order through its presiding spirit Duk-Duk, a mysterious figure dressed in leaves to its waist, with a helmet like a gigantic candle-extinguisher made of network. Upon this figure women and children are forbidden to look. Women, who are entitled in New Britain to their own earnings and work harder than men, are the special victims of Duk-Duk, who levies blackmail upon them if they are about during its visits. These are generally timed to coincide with the hours at which the women are out in the fields and therefore cannot help seeing the figure. Justice is executed, fines extorted, taboos, feasts, taxes and all tribal matters are arranged by the Duk-Duk members, who wear hideous masks or chalk their faces. In carrying out punishments they are allowed to burn houses and even kill people. Only males can belong to Duk-Duk, the entrance fees of which vary from 50 to 100 fathoms of _dewarra_ (small cowrie shells strung on strips of cane). The society has its secret signs and ritual, and festivals at which the presence of a stranger would mean his death. Duk-Duk only appears with the full moon. The society is now much discredited and is fast dying out.