Part 11

DUHAMEL DU MONCEAU, HENRI LOUIS (1700-1782), French botanist and engineer, son of Alexandre Duhamel, lord of Denainvilliers, was born at Paris in 1700. Having been requested by the Academy of Sciences to investigate a disease which was destroying the saffron plant in Gatinais, he discovered the cause in a parasitical fungus which attached itself to the roots, and this achievement gained him admission to the Academy in 1728. From then until his death he busied himself chiefly with making experiments in vegetable physiology. Having learned from Sir Hans Sloane that madder possesses the property of giving colour to the bones, he fed animals successively on food mixed and unmixed with madder; and he found that their bones in general exhibited concentric strata of red and white, whilst the softer parts showed in the meantime signs of having been progressively extended. From a number of experiments he was led to believe himself able to explain the growth of bones, and to demonstrate a parallel between the manner of their growth and that of trees. Along with the naturalist Buffon, he made numerous experiments on the growth and strength of wood, and experimented also on the growth of the mistletoe, on layer planting, on smut in corn, &c. He was probably the first, in 1736, to distinguish clearly between the alkalis, potash and soda. From the year 1740 he made meteorological observations, and kept records of the influence of the weather on agricultural production. For many years he was inspector-general of marine, and applied his scientific acquirements to the improvement of naval construction. He died at Paris on the 13th of August 1782.

His works are nearly ninety in number, and include many technical handbooks. The principal are:--_Traite des arbres et arbustes qui se cultivent en France en pleine terre_; _Elements de l'architecture navale_; _Traite general des peches maritimes et fluviatiles_; _Elements d'agriculture_; _La Physique des arbres_; _Des Semis et plantations des arbres et de leur culture_; _De l'exploitation des bois_; _Traite des arbres fruitiers_.

DUHRING, EUGEN KARL (1833-1901), German philosopher and political economist, was born on the 12th of January 1833 at Berlin. After a legal education he practised at Berlin as a lawyer till 1859. A weakness of the eyes, ending in total blindness, occasioned his taking up the studies with which his name is now connected. In 1864 he became _docent_ of the university of Berlin, but, in consequence of a quarrel with the professoriate, was deprived of his licence to teach in 1874. Among his works are _Kapital und Arbeit_ (1865); _Der Wert des Lebens_ (1865); _Naturliche Dialektik_ (1865); _Kritische Geschichte der Philosophie_ (1869); _Kritische Geschichte der allgemeinen Principien der Mechanik_ (1872)--one of his most successful works; _Kursus der National- und Sozialokonomie_ (1873); _Kursus der Philosophie_ (1875), entitled in a later edition _Wirklichkeitsphilosophie; Logik und Wissenschaftstheorie_ (1878); _Der Ersatz der Religion durch Vollkommeneres_ (1883). He published his autobiography in 1882 under the title _Sache, Leben und Feinde_; the mention of "Feinde" (enemies) is characteristic. Duhring's philosophy claims to be emphatically the philosophy of reality. He is passionate in his denunciation of everything which, like mysticism, tries to veil reality. He is almost Lucretian in his anger against religion which would withdraw the secret of the universe from our direct gaze. His "substitute for religion" is a doctrine in many points akin to Comte and Feuerbach, the former of whom he resembles in his sentimentalism. Duhring's opinions changed considerably after his first appearance as a writer. His earlier work, _Naturliche Dialektik_, in form and matter not the worst of his writings, is entirely in the spirit of the Critical Philosophy. Later, in his movement towards Positivism, he strongly repudiates Kant's separation of phenomenon from noumenon, and affirms that our intellect is capable of grasping the whole reality. This adequacy of thought to things is due to the fact that the universe contains but one reality, i.e. matter. It is to matter that we must look for the explanation both of conscious and of physical states. But matter is not, in his system, to be understood with the common meaning, but with a deeper sense as the substratum of all conscious and physical existence; and thus the laws of being are identified with the laws of thought. In this materialistic or quasi-materialistic system Duhring finds room for teleology; the end of Nature, he holds, is the production of a race of conscious beings. From his belief in teleology he is not deterred by the enigma of pain; he is a determined optimist. Pain exists to throw pleasure into conscious relief. In ethics Duhring follows Comte in making sympathy the foundation of morality. In political philosophy he teaches an ethical communism, and attacks the Darwinian principle of struggle for existence. In economics he is best known by his vindication of the American writer H.C. Carey, who attracts him both by his theory of value, which suggests an ultimate harmony of the interests of capitalist and labourer, and also by his doctrine of "national" political economy, which advocates protection on the ground that the morals and culture of a people are promoted by having its whole system of industry complete within its own borders. His patriotism is fervent, but narrow and exclusive. He idolized Frederick the Great, and denounced Jews, Greeks, and the cosmopolitan Goethe. Duhring's clear, incisive writing is disfigured by arrogance and ill-temper, failings which may be extenuated on the ground of his physical affliction. He died in 1901.

See H. Druskowitz, _Eugen Duhring_ (Heidelberg, 1888); E. Doll, _Eugen Duhring_ (Leipzig, 1892); F. Engels, _Eugen D.'s Umwalzung der Wissenschaft_ (3rd ed., Stuttgart, 1894); H. Vaihinger, _Hartmann, Duhring und Lange_ (1876). (H. St.)

DUIGENAN, PATRICK (1735-1816), Irish lawyer and politician, was the son of a Leitrim Roman Catholic farmer named O'Duibhgeannain. Through the tuition of the local Protestant clergyman, who was interested in the boy, he got a scholarship in 1756 at Trinity College, Dublin, and subsequently became a fellow. He was called to the Irish bar in 1767 and obtained a rich practice. He is remembered, however, mainly as a politician, on account of his opposition to Grattan, his support of the Union, and his violent antagonism to Catholic emancipation. He was elected member for Armagh in the first united parliament, and was a well-known character at Westminster till he died on the 11th of April 1816.

DUIKER (diver), or DUIKERBOK, the Dutch name of a small S. African antelope, scientifically known as _Cephalophus grimmi_; the popular name alluding to its habit of diving into and threading its way through thick bush. Scientifically the name is extended to include all the members of the African genus _Cephalophus_, which, together with the Indian chousingha, or four-horned antelope (_Tetraceros_), constitutes the subfamily _Cephalophinae_. Duikers are animals of small or medium size, usually frequenting thick forest. The horns, usually present in both sexes, are small and straight, situated far back on the forehead; and between them rises the crest-like tuft of hair from which the genus takes its scientific name. The common or true duiker (_C. grimmi_) is found in bush-country from the Cape to the Zambezi and Nyasaland, and ranges northward on the west coast to Angola. The banded duiker (_C. doriae_) from West Africa is golden brown with black transverse bands on the back and loins. _C. sylvicultor_, of West Africa, is the largest species, and approaches a donkey in size. (See ANTELOPE.) (R. L.*)

DUILIUS (or DUELLIUS), GAIUS, Roman general during the first Carthaginian War and commander in the first Roman naval victory. In 260 B.C., when consul in command of the land forces in Sicily, he was appointed to supersede his colleague Cn. Cornelius Scipio Asina, commander of the fleet, who had been captured in the harbour of Lipara. Recognizing that the only chance of victory lay in fighting under conditions as similar as possible to those of a land engagement, he invented a system of grappling irons (_corvi_) and boarding bridges, and gained a brilliant victory over the Carthaginian fleet off Mylae on the north coast of Sicily. He was accorded a triumph and the distinction of being accompanied, when walking in the streets during the evening, by a torchbearer and a flute-player. A memorial column (_columna rostrata_), adorned with the beaks of the captured ships, was set up in honour of his victory. The inscription upon it (see LATIN LANGUAGE, section 3, "The Language as Recorded") has been preserved in a restored form in pseudo-archaic language, ascribed to the reign of Claudius.

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 Dusseldorf, 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.

See "Duk-Duk and other Customs or Forms of Expression of the Melanesian's Intellectual Life," by Graf von Pfeil (_Journ. of Anthrop. Instit._ vol. 27, p. 181).

DUKE (corresponding to Fr. _duc_, Ital. _duca_, Ger. _Herzog_), the title of one of the highest orders of the European nobility, and of some minor sovereign princes. The word "duke," which is derived from the Lat. _dux_, a leader, or general, through the Fr. _duc_ (O. Fr. _dusc_, _ducs_, _dus_), originally signified a leader, and more especially a military chief, and in this latter sense was the equivalent of the A.S. _heretoga_ (_here_, an army, and _teon_, from _togen_, to draw; Ger. _ziehen_, _zog_; Goth, _tiuhan_; Lat. _ducere_) and the old Ger. _herizog_. In this general sense the word survived in English literature until the 17th century, but is now obsolete.

The origin of modern dukes is twofold. The _dux_ first appears in the Roman empire under the emperor Hadrian, and by the time of the Gordians has already a recognized place in the official hierarchy. He was the general appointed to the command of a particular expedition and his functions were purely military. In the 4th century, after the separation of the civil and military administrations, there was a duke in command of the troops quartered in each of the frontier provinces of the empire, e.g. the _dux Britanniarum_. The number of dukes continually increased, and in the 6th and 7th centuries there were _duces_ at Rome, Naples, Rimini, Venice and Perugia. Gradually, too, they became charged with civil as well as military functions, and even exercised considerable authority in ecclesiastical administration. Under the Byzantine emperors they were the representatives in all causes of the central power. The Roman title of duke was less dignified than that of count (_comes_, companion) which implied an honourable personal relation to the emperor (see COUNT). Both titles were borrowed by the Merovingian kings for the administrative machinery of the Frank empire, and under them the functions of the duke remained substantially unaltered. He was a great civil and military official, charged to watch, in the interests of the crown, over groups of several _comitatus_, or countships, especially in the border provinces. The sphere of the dukes was never rigidly fixed, and their commission was sometimes permanent, sometimes temporary. Under the Carolingians the functions of the dukes remained substantially the same; but with the decay of the royal power in the 10th century, both dukes and counts gained in local authority; the number of dukes became for the time fixed, and finally title and office were made hereditary, the relation to the crown being reduced to that of more or less shadowy vassalage. (See FEUDALISM.)

Side by side with these purely official dukedoms, however, there had continued to exist, or had sprung up, either independently or in more or less of subjection to the Frank rulers, national dukedoms, such as those of the Alemanni, the Aquitanians, and, later, of the Bavarians and Thuringians. These were developed from the early Teutonic custom by which the _herizog_ was elected by the nation as leader for a particular campaign, as in the case of the _heretogas_ who had led the first Saxon invaders into Britain. Tacitus says of the ancient Germans _reges ex nobilitate, duces ex virtute sumunt_; i.e. they elected their dukes for their warlike prowess only, and as purely military chiefs, whereas their kings were chosen from a royal family of divine descent. Sometimes the dukes so chosen succeeded in making their power permanent without taking the style of king. To this national category belong, besides the great German dukedoms, the dukes of Normandy, and the Lombard dukes of Spoleto and Benevento, who traced their origin, not to an administrative office, but to the leadership of Teutonic war bands. With the development of the feudal system the distinction between the official and the national dukedoms was more and more obliterated. By the 13th and 14th centuries the title had become purely territorial, and implied no necessary overlordship over counts and other nobles, who existed side by side with the dukes as tenants-in-chief of the crown. From this time the significance of the ducal title varies widely in different countries. Whenever the crown got the better of the feudal spirit of independence, as in France or Naples, it sank from being a sovereign title to a mere social distinction, implying no political power, and not necessarily any territorial influence. In northern Italy and in Germany, on the other hand, where the crown had proved too weak to combat the forces of disruption, it came ultimately to imply independent sovereignty.

The abolition of the Holy Empire in 1806 removed even the shadow of vassalage from the German reigning dukes, who retain their sovereign status under the new empire. Only one, however, the grand duke of Luxemburg, is now both sovereign and independent. Besides the sovereign dukes in Germany there are certain "mediatized" ducal houses, e.g. that of Ratibor, which share with the dispossessed families of the Italian sovereign duchies certain royal privileges, notably that of equality of blood (_Ebenburtigkeit_). In Italy, where titles of nobility give no precedence at court, that of duke (_duca_) has lost nearly all even of its social significance owing to lavish creations by the popes and minor sovereigns, and to the fact that the title often passes by purchase with a particular estate. Political significance it has none. Some great Italian nobles are dukes, notably the heads of the great Roman ducal families, but not all Italian dukes are great nobles.

In France the title duke at one time implied vast territorial power, as with the dukes of Burgundy, Normandy, Aquitaine and Brittany, who asserted a practical independence against the crown, though it was not till the 12th century that the title duke was definitely regarded as superior to others. At first (in the 10th and 11th centuries) it had no defined significance, and even a baron of the higher nobility called himself in charters duke, count or even marquis, indifferently. In any case the strengthening of the royal power gradually sapped the significance of the title, until on the eve of the Revolution it implied no more than high rank and probably territorial wealth.

There were, under the _ancien regime_, three classes of dukes in France: (1) dukes who were peers (see PEERAGE) and had a seat in the parlement of Paris; (2) hereditary dukes who were not peers; (3) "brevet" dukes, created for life only. The French duke ranks in Spain with the "grandee" (q.v.), and vice versa. In republican France the already existing titles are officially recognized, but they are now no more than the badges of distinguished ancestry. Besides the descendants of the feudal aristocracy there are in France certain ducal families dating from Napoleon I.'s creation of 1806 (e.g. ducs d'Albufera, de Montebello, de Feltre), from Louis Philippe (duc d'Isly, and duc d'Audiffret-Pasquier), and from Napoleon III. (Malakoff, Magenta, Morny).

In England the title of duke was unknown till the 14th century, though in Saxon times the title ealdorman, afterwards exchanged for "earl," was sometimes rendered in Latin as _dux_,[1] and the English kings till John's time styled themselves dukes of Normandy, and dukes of Aquitaine even later. In 1337 King Edward III. erected the county of Cornwall into a duchy for his son Edward the Black Prince, who was thus the first English duke. The second was Henry, earl of Lancaster, Derby, Lincoln and Leicester, who was created duke of Lancaster in 1351. In Scotland the title of duke was first bestowed in 1398 by Robert III. on his eldest son David, who was made duke of Rothesay, and on his brother, who became duke of Albany.

British dukes rank next to princes and princesses of the blood royal, the two archbishops of Canterbury and York, the lord Chancellor, &c., but beyond this precedence they have no special privileges which are not shared by peers of lower rank (see PEERAGE). Though their full style as proclaimed by the herald is "most high, potent and noble prince," and they are included in the _Almanach de Gotha_, they are not recognized as the equals in blood of the crowned or mediatized dukes of the continent, and the daughter of an English duke marrying a foreign royal prince can only take his title by courtesy, or where, under the "house-laws" of certain families, a family council sanctions the match. The eldest son of an English duke takes as a rule by courtesy the second title of his father, and ranks, with or without the title, as a marquess. The other sons and daughters bear the titles "Lord" and "Lady" before their Christian names, also by courtesy. A duke in the British peerage, if not royal, is addressed as "Your Grace" and is styled "the Most Noble." (See ARCHDUKE, GRAND DUKE, and, for the ducal coronet, CROWN AND CORONET.) (W. A. P.)

FOOTNOTE:

[1] So _Ego Haroldus dux, Ego Tostinus dux_, in a charter of Edward the Confessor (1060), Hist. MSS. Comm. 12th rep. app. pt. ix. p. 581.

DUKE OF EXETER'S DAUGHTER, a nickname applied to a 15th-century instrument of torture resembling the rack (q.v.). Blackstone says (_Commentaries_, ii. sec. 326): "The trial by rack is utterly unknown to the law of England, though once when the dukes of Exeter and Suffolk, and other ministers of Henry VI., had laid a design to introduce the civil (i.e. Roman) law into the kingdom as the rule of government, for a beginning thereof they erected a rack for torture, which was called in derision the duke of Exeter's daughter, and still remains in the Tower of London, where it was used as an engine of state, not of law, more than once in Queen Elizabeth's reign. But when, upon the assassination of Villiers, duke of Buckingham, by Felton, it was proposed in the privy council to put the assassin to the rack, in order to discover his accomplices, the judges being consulted, declared unanimously that no such proceeding was allowable by the laws of England."

DUKER, CARL ANDREAS (1670-1752), German classical scholar and jurist, was born at Unna in Westphalia. He studied at the university of Franeker under Jacob Perizonius. In 1700 he was appointed teacher of history and eloquence at the Herborn gymnasium, in 1704 vice-principal of the school at the Hague, and in 1716 he succeeded (with Drakenborch as colleague) to the professorship formerly held by Peter Burmann at Utrecht. After eighteen years' tenure he resigned his post, and lived in retirement at Ysselstein and Vianen. His health finally broke down under excessive study, and he died, almost blind, at the house of a relative in Meiderich near Duisburg, on the 5th of November 1752. His chief classical works were editions of Florus (1722) and Thucydides (1731, considered his best). He brought out the 2nd edition of Perizonius's _Origines Babylonicae et Aegyptiacae_ (1736) and his commentary on Pomponius Mela (1736-1737). Duker was also an authority on ancient law, and published _Opuscula varia de latinitate veterum jurisconsultorum_ (1711), and a revision of the _Leges Atticae_ of S. Petit (1741).

See C. Saxe, _Onomasticon litterarium_, vi. 267; articles in _Allgemeine deutsche Biographie_ and in Ersch and Gruber's _Allgemeine Encyklopadie_.

DUKERIES, THE, a name given to a district in the N.W. of Nottinghamshire, England; included within the ancient Sherwood Forest (q.v.). The name is taken from the existence of several adjacent demesnes of noblemen, and the character of the Forest is to some extent preserved here. On the north is the Sheffield-Retford branch of the Great Central railway, serving the town of Worksop, connecting at Retford with the Great Northern railway, while on the south the Great Central railway serves the small market town of Ollerton, and connects with the Great Northern at Dukeries Junction. The following demesnes are comprised in the district. Worksop Manor formerly belonged to the dukes of Norfolk. Welbeck Abbey is the seat of the dukes of Portland, to whom it came from the Cavendish family (dukes of Newcastle); the mansion is mainly classic in style, dating from the early 17th century, but with many subsequent additions; the fifth duke of Portland (d. 1879) built the curious series of subterranean corridors and chambers beneath the grounds. Clumber House, the seat of the dukes of Newcastle, is beautifully placed above a lake in a fine park. Thoresby House is the seat of the earls Manvers, to whom it came on the extinction of the dukedom of Kingston; part of this demesne is a splendid tract of wild woodland.