DurgaDurga
Durga(du¨r´gä), a Hindu divinity, one of the names given to the consort of Siva. She is generally represented with ten arms. In one hand she holds a spear, with which she is piercing Mahisha, the chief of the demons, the killing of whom was her most famous exploit; in another a sword; in a third the hair of the demon chief; and in others, the trident, discus, axe, club, and shield. A great festival in her honour, theDurga puja, is celebrated annually, lasting for ten days.
Durham, Simeon of, English chronicler of the twelfth century; wroteAnnals of England to the Reign of Henry I, particularly valuable for events connected with the north of England. They were continued by John of Hexham.
Durham(du´ram), an ancient city, capital of the county of the same name, on the River Wear, which is crossed here by four bridges, 14 milesS.of Newcastle. The principal public buildings are the ancient castle—now appropriated to the uses of the university—the cathedral and other churches, the town hall, county prison, and grammar-school. The educational institutions comprise the university, opened in 1833, the grammar-school, a training-school for school-mistresses, and other schools. There are manufactures of carpeting and mustard. The cathedral occupies a height overlooking the Wear. The larger portion of it is Norman in style, with insertions in all the English styles. Three magnificent and elaborately ornamental towers spring up from the body of the building, one from the centre 212 feet high, and two together from the west end each 143 feet high; the entire length is 420 feet. It was founded by William de St. Carilef, assisted by Malcolm, King of Scotland, in 1093. A parliamentary borough until 1918, Durham returned two members to the House of Commons from 1673 to 1885, and one member from 1885 to 1918. Pop. 17,500.
Durham Book, a Latin text of the gospels written by Bishop Eadfrith of Lindisfarne, with an interlinear Saxon gloss, finished in the year 720; now in the British Museum.
Durham, County of, a county on theN.E.coast of England, having on theE.the North Sea, on theN.Northumberland, from which it is divided by the Rivers Tyne and Derwent, Cumberland on theW., and Yorkshire on theS., the River Tees parting the two counties. Its area is 647,592 acres, of which two-thirds are under cultivation. The western portion of the county is hilly, enclosing fertile valleys, the eastern portion is more level, and the centre contains extensive coal-fields. Durham is the chief coal county in England, and also produces fire-clay. The chief crops are wheat, oats, turnips, and potatoes. The cattle are esteemed both for the dairy and for fattening. In connection with the commerce of the county may be noticed its foundries, ironworks, potteries, glass-houses, iron-shipbuilding, engine and machine works, and chemical works. For parliamentary purposes it is divided into eleven divisions, each of which sends one member to the House of Commons. It was formerly one ofthe three counties called countiespalatine. The chief towns besides Durham are Sunderland, Gateshead, South Shields, Stockton, Darlington, and Hartlepool. Pop. 1,369,860.— Cf.Victoria History of the County of Durham.
Durham University, founded in 1832, opened in 1833, incorporated by royal charter in 1837. It is connected with the bishopric of Durham, the office of warden being annexed to the deanery of Durham, and a canonry in the cathedral being annexed to each of the professors of divinity and classical literature. There are also professors of mathematics, Hebrew, medicine, &c. The students mostly reside within the university buildings, but in 1870 a regulation was passed dispensing with the necessity of residing in any college, hall, or house connected with the university in order to be admitted as a member. The management of the university is entrusted, under the Bishop of Durham as visitor, to the dean and chapter of the cathedral as governors, and to the warden, senate, and convocation, the last including all persons regularly admitted since the opening of the university to the degrees of Doctor in Divinity, Civil Law, and Medicine, and to the degree of Master of Arts. The academical year is divided into three terms—Michaelmas, Epiphany, and Easter. For the degree ofB.A., or a licence in theology, a residence of two years (of six months each) is necessary. TheM.A.degree may be obtained by a graduate who is of the standing of nine terms since taking his degree ofB.A.Armstrong College, founded in 1874, and the College of Medicine, both at Newcastle-on-Tyne, form part of the University of Durham.
DurianDurian and Section of Fruit
Durian, orDurion(Durio zibethīnus), a large and lofty tree growing in the Malayan Archipelago. The largish flowers, of a yellow-green colour, are produced on the stem or main branches, and are followed by the large fetid fruit, which is of the size of a man's head, and is a favourite food of the natives during the time (May and June) when it is in season. There is usually a second crop in November. The smell is offensive, like putrid animal matter, but with this is associated the most delicious flavour, which places it, notwithstanding the odour, in the opinion of many, in the foremost place among tropical fruits.
Dürkheim(du˙rk´hīm), an old town in Rhenish Bavaria (the Palatinate), 14 milesW.S.W.of Mannheim, well known for its mineral water. The town was destroyed by the French in 1689. Pop. 6523.
Durkheim, Émile, French philosopher and sociologist, born at Les Vosges 15th April, 1858, died in Paris 15th Nov., 1917. Educated at the École Normale Supérieure, he travelled in Germany, where he studied social conditions. In 1887 he founded the first French chair in sociology at the University of Bordeaux. Durkheim's merit consists in having separated sociology from mere psychology, and in having made a distinction between individual mental phenomena and Folk-psychology. In 1898 he founded and published annuallyL'Année Sociologique. His other works include:De la division du travail social(1893);Les règles de la méthode sociologique(1894);Le Suicide(1897);Les formes élémentaires de la vie réligieuse; Sociologie et sciences sociales(1910);Le système totémique en Australie(1912);La Sociologie(inLa Science Française, 1915);Qui a voulu la guerre?; Les Origines de la guerre, d'après les documents diplomatiques(1915).
Durlach(du¨r´la˙h), a town in Baden, 4 milesE.S.E.of Carlsruhe, at the foot of the Turmberg, with manufactures of machinery, chemicals, and leather. Pop. 13,896.
Durmast, a species of oak,Quercus sessiliflora, or according to some,Q. pubescens, so closely allied to the common oak (Q. robur) as to be reckoned only a variety of it. Its wood is, however, darker, heavier, and more elastic, less easy to split, not so easy to break, yet not so difficult to bend. It is highly valued, therefore, by the builder and cabinet-maker.
Duroc(du˙-rok), Michel Géraud Christophe, Duke of Friuli, a distinguished general under Bonaparte, born at Pont-à-Mousson in 1772, killed, 1813, at the battle of Bautzen. He served as aide-de-camp to Napoleon in the Italian and Egyptian campaigns. In 1805 he was made grand-marshal of the palace; and was frequently employed in diplomatic missions, though he stilltook his full share in the wars of France till the time of his death. He was a great favourite of Napoleon, and was killed by his side.
Durra, orDhurra, Indian millet, the seed ofSorghum vulgāre, after wheat the chief cereal crop of the Mediterranean region, and largely used in those countries by the labouring classes for food. Varieties are grown in many parts of Africa, one of them being known as Kaffir corn.
Dürrenstein(du˙r´en-stīn), a village in Lower Austria, on the Danube, 41 miles west by north of Vienna. Here are the ruins of the castle in which Leopold, Duke of Austria, imprisoned Richard Cœur-de-Lion on his return from Palestine, 1192.
Duruy(du˙-ru˙-ē), Victor, French historian and educationist, born at Paris 1811, died in 1894. His father was a workman in the Gobelins tapestry works, and the boy did not begin his education until he was grown up. He was admitted to the École Normale Supérieure in 1830, graduated in 1833, and was appointed successively teacher of history in the Lycée Henri IV, then at the Normal School and the Polytechnic School, inspector of the Academy of Paris, inspector-general of secondary education, and Minister of Public Instruction (1863-9). He is author ofGéographie Politique de la République Romaine et de l'Empire,Géographie Historique du Moyen Age,Histoire Romaine,Histoire de France,Histoire Grecque,Histoire Populaire Contemporaine, &c. Some of these are simply school-books, but hisHistoire des Romains(translated into English) and hisHistoire de la Grèce Ancienne(translated into English) are extensive and important works, the former especially.
Duse, Eleonora, Italian actress, born at Vigevano, near Venice, in 1859. At the age of thirteen she made her first appearance on the stage, and in 1883 she acted at Rome, when she was recognized as one of the greatest Italian, and even one of the greatest living actresses. From that time her career was one of uninterrupted success, and she gained a world-wide reputation. Duse is one of the dramatic artists who discard the customary mannerisms of the stage, and all that is conventional but unreal in modern acting. Some of d'Annunzio's best plays were specially written for her. Among her most remarkable impersonations are those of Francesca da Rimini, Marguerite Gautier inLa Dame aux Camélias, Magda, La Tosca, Paula inThe Second Mrs. Tanqueray, and Nora in Ibsen'sA Doll's House. She appeared for the first time in London in 1897.
Düsseldorf(du˙s´sel-dorf), a town of Germany, in the Rhine province, beautifully situated among villas and gardens on the right bank of the Rhine, 22 milesN.N.W.of Cologne, one of the handsomest towns in the valley of the Rhine. It is a great focus of railway and steamboat communication, and has a number of handsome public buildings, and several remarkable churches. Among the public institutions particular notice is due to the Academy of Art, founded in 1767, by the Elector Theodore, and afterwards directed by Cornelius, Schadow, and Bendemann. It has the honour of having founded a school of painting, which takes the name of Düsseldorf, and has had a large number of distinguished pupils. The industries embrace iron, machinery, railway plant, cotton, leather, chemicals, and beer, and the trade is large. Pop. 358,728.
Dust, solid matter in a fine state of division. Spores of plants, bacteria, &c., are found in the atmosphere, but in general organic particles are numerous only over thickly populated districts. Inorganic particles are derived from various sources. Where the soil is dry, dust is whirled aloft by the winds, this cause giving rise to the great sand-storms of tropical desert regions. Volcanoes in eruption eject large quantities of dust. It is estimated that millions of meteors are encountered by the earth per day. Most of these are excessively minute. They are speedily disintegrated, and generally entirely reduced to dust at high levels. Evaporation is almost always proceeding over seas and oceans, and from foam thrown up and swept along by the winds the dissolved salts are liberated as solid particles. Again vast quantities of dust are produced in the consumption of fuel.
The late Dr. John Aitken,F.R.S., of Falkirk, Stirlingshire, contrived a means of gauging the dust contents of the atmosphere. This consists of a glass box about a centimetre in thickness. Two pieces of wet filter paper inside serve to keep the contained air damp. The bottom of the box is a micrometer plate, divided rectangularly in millimetres. It can be examined from above by a lens. An air-pump can withdraw definite volumes of air as desired. When the air is partially withdrawn, the expansion of the remainder produces cooling. The dust particles form nuclei for condensation of the vapour. They are thus precipitated on the plate, and counted, leaving the air dust-free. A measured quantity of the air to be tested is next drawn in and shaken up. Further operation of the air-pump causes its expansion, and the deposition of its dust particles, which can then be counted. Dr. Aitken found the proportion of dust on Ben Nevis to vary at different times from under 100 particles to over 14,000 per cubic centimetre. Over oceans the numbers were from about 500 on the Indian to 2000 on the Atlantic. But over cities 100,000 per cubic centimetre are frequently present. A puff of cigarette smoke was estimated to contain 4,000,000,000 particles.
Many phenomena are connected with the existence of dust in the atmosphere. As a result of Dr. Aitken's discoveries the belief largely prevailed that the formation of fog, of rain, and other varieties of precipitation, was necessarily dependent on dust particles as nuclei of condensation. Though they certainly function to a preponderating extent, it has been shown that gaseous particles can act similarly, particularly when air is ionized. Dust is the main cause of the scattering of the sun's rays which produces twilight, the blue of the sky, the gorgeous red and golden hues of sunrise and sunset, and the purple lights of advancing dusk. After the great Krakatoan eruptions of 1883, dust was carried in the upper atmosphere several times round the earth, and caused extraordinary colour effects. To a lesser degree similar phenomena followed the West Indian eruptions of 1902. The unusual sunlessness of the summer of 1912 was attributed to dust expelled in the preceding great eruptions at Katmai, Alaska.
Dutch Clover,Trifolium repens, commonly called white clover, a valuable pasture plant. It has a creeping stem; the leaflets are broad, obovate, with a horse-shoe mark in the centre; the white or pinkish flowers are in a globular head.
Dutch East Indies, forming a large and important colonial possession of the Netherlands Government, lie between 6°N.and 11°S., and 95°E.and 141°E.The colony includes Java and Madura, with the 'Outposts', which comprise Sumatra, the south-east and west portions of Borneo, Banca, Billiton, Celebes, the Timor and Riau-Lingga Archipelagos, the smaller Sunda Islands, and the north and west of New Guinea. The total area is about 735,000 sq. miles; the population of about 47,000,000 is composed of 46,000,000 natives of Malay race, 832,000 Arabs, Chinese, and other Orientals, and some 80,000 whites. The origin of the colony may be traced to the treaty made by the Dutch with the Sultan of Bantam in Sumatra (1595), which was followed by the formation of the Dutch East India Company (1602), the establishment of Batavia (1619) on the ruins of the native town of Jacatra, and the settlement in Sumatra (1677). The Dutch East India Company was dissolved in 1798, since which date the colony has been administered from the Netherlands by a Governor-General, who, assisted by a Council of five members nominated by the queen, has the power to pass laws, subject to the general regulations adopted in 1854. Some of the outlying islands are, however, administered by their native princes under the 'advice' of a Netherlands Resident. Batavia (population about 234,000), a town in the province of the same name on the north-west coast of Java, is the administrative capital and an important centre of trade. Java and Sumatra, containing about three-fourths of the total population of the colony, are self-supporting as regards food, besides producing for European consumption large quantities of tobacco, tea, coffee, sugar, cinchona, tin, rubber, and copra. The colonial army numbers some 1200 officers and 40,000 men; compulsory service for white men within certain age-limits was adopted in 1918. There is also a small naval force.—Bibliography: Bemmelen and Hooyer,Guide to the Dutch East Indies; W. Cool,With the Dutch in the East; J. M. Brown,The Dutch East.
Dutch Metal, an alloy containing 84.5-84.7 per cent of copper and 15.5-15.3 per cent of zinc, with a fine golden-yellow colour, ductile, malleable, and tenacious. When beaten out by a process analogous to that for gold-leaf, until the sheets are less than 1/50,000th part of an inch thick, it constitutes Dutch leaf or Dutch foil, and is used as a cheap substitute for gold-leaf for ornamental purposes.
Dutch Pink, a bright yellow colour used in distemper, for staining paper-hangings, and for other ordinary purposes. It is composed of chalk or whiting coloured with a decoction of birch leaves, French berries, and alum.
Dutch Rush,Equisētum hyemāle, one of the plants known as horse-tails, with a firm texture and so large an amount of silica in the cuticle that it is employed as a fine sand-paper for polishing delicate woodwork. The plant is found in marshes and woods in Britain, but for economic use it is imported from Holland, whence its popular name.
Dutrochet(du˙-tro-shā), René Joachim Henri, a French physiologist, born in Poitou in 1776, died at Paris in 1847. He served for some time as medical attendant to Joseph Bonaparte during the Spanish campaign 1808-9; but afterwards returned to France, and retired to the estate of Châteaurenault, where he devoted himself exclusively to physical and physiological studies. His chief works have been published in a collective form with the titleMémoires pour servir à l'Histoire Anatomique et Physiologique des Végétaux et des Animaux(1837, 2 vols.).
Dvina, Northern, a Russian river formed by the union of two small streams in the government of Vologda. It flows in a north-westerly direction, and falls by four mouths into the White Sea. At Archangel, before it divides, it is 4 miles broad. It is navigable as far as Suchona, and is connected with the Volga and Neva by canal.
Dvořák(dvor-shäk´), Anton, a Bohemian musical composer, born in 1841, died in 1904. He studied at the Prague Conservatoire, and composed several operas on national Bohemian subjects, songs, orchestral arrangements of Bohemian dances, several symphonies, aStabatMater, a cantata (The Spectre Bride), and an oratorio (St. Ludmila). In 1892 he was director of the New York National Conservatory, and after 1895 he lived in Prague, where he wrote, in 1889, the operaDer Teufel und die wilde Kätze.
Dwarf, a term applied to any animal or plant greatly below the usual size of its kind, particularly to a human being of small dimensions. Strictly speaking, the term should be used with reference to individuals and not to races. When a whole population consists of people of small stature, the proper term to apply to them is pigmies, not dwarfs. Accounts of pigmy tribes have been common from early times, such tribes being located especially in Africa; and it would appear from the accounts of Du Chaillu, Schweinfurth, and other travellers that there are several pigmy tribes throughout this continent. The Obongo, a race of dwarfs, are described as living in woods near the Okanda River, in wretched huts made of branches. Other races are the Mabongo, and the Akka dwarfs of Central Africa (seeAkkas); and a race exists in the Congo State, not as a distinct community, however, but mixed with other tribes. Individual dwarfs occur in all races, and were formerly a fashionable appendage to the courts of princes and the families of nobles. Jeffery Hudson, the favourite dwarf of Charles I, at the age of thirty is said to have been only 18 inches high, though he afterwards grew to 3 feet 9 inches. Bébé, the celebrated dwarf of Stanislas of Poland, was 33 inches; Wybrand Lolkes, a Dutch dwarf, when sixty years of age was only 27 inches; Charles H. Stratton, 'General Tom Thumb', was 31 inches high at the age of twenty-five; Francis Flynn, 'General Mite', was only 21 inches at sixteen. In most of the extreme cases the dwarfing is the result of some defect in the ductless glands which regulate the normal growth of the body. Stories of dwarfs and brownies are to be found in the folk-lore of many tribes on earth.—Bibliography: E. J. Wood,Giants and Dwarfs; E. Tyson,Philological Essay concerning Pygmies of the Ancients.
Dwarfing, the process of training up trees or shrubs for ornament in houses so as to cause them never to reach more than a very small size, by keeping them in poor soil, giving them little water, pinching off strong shoots, &c. It is much practised among the Chinese and Japanese.
Dwight(dwīt), Timothy, American divine, born in Massachusetts 1752, died 1817. His father was Colonel Timothy Dwight, and his mother was a daughter of Jonathan Edwards. He served as chaplain in the revolutionary army, and ultimately became president of Yale College. HisTheology Explained and Defended(1818) was for long a standard work both in Britain and in America.
Dy´aks, the aborigines of Borneo, chiefly inhabiting the interior of the island. They are a finely formed race, of a yellow complexion, and are described as docile, industrious, and superior to the Malays. The more advanced of them practise agriculture and dwell in neatly-constructed and tolerably comfortable houses. In Sarawak they have made considerable advances in civilization. The practice of head-hunting (hunting their enemies to make trophies of their heads) is practised among them, but has been abolished where European influence prevails.—Cf. Hose and M‘Dougall,The Pagan Tribes of Borneo(2 vols.).
Dyaus(dyous), the god of the sky in the older mythology of the Hindus. His name is etymologically connected with that of the Greek Zeus.
Dyce(dīs), Alexander, Shakespearean editor, born at Edinburgh 30th June, 1798, died 15th May, 1869. He was educated at Edinburgh and Oxford, but in 1827 settled in London, where most of his life was passed. He first became known by his editions of Collins, Peele, Webster, Marlowe, and Skelton, accompanied by notes and biographies of the authors. His chief work was an edition of Shakespeare in six volumes, with notes (1853-8).
Dyce, William, painter, born at Aberdeen in 1806, died near London, 1864. He studied in London and Rome, and practised his art in Edinburgh. In 1840 he became director of the School of Design in London, and in 1844 was appointed professor of fine art in King's College, London. He was elected a Royal Academician in 1848. Amongst his chief works are:Francesca da Rimini(1837):Joash shooting the Arrow of Deliverance(1844);King Lear in the Storm(1851);Christabel(1855);The Good Shepherd(1856);The Baptism of Ethelbert, a large fresco for the Houses of Parliament, and a series of frescoes illustrative of the legends relating to King Arthur, for the same. He also executed for the Prince Consort, at Osborne, the frescoNeptune giving the Empire of the Sea to Britannia.
Dyeingis the art of colouring textile and other materials in such a way that the colours are not readily removed by the action of light, washing, &c. Like spinning and weaving, it was originally a home industry, as it still is in many places. The natural dyes formerly employed are now largely displaced by dyes derived from coal-tar products, the first discovery of which was made by Perkin in 1856; a few mineral colours are employed in cotton dyeing. Before dyeing, the materials have generally to be cleansed or bleached to get rid of undesirable colouring matters or impurities; and frequently a textile material is subjected to some subsidiary treatment in order to obtain special effects. For example, cotton yarn may be subjected tothe action of strong caustic soda ('mercerizing' process) while in a state of great tension, in order to give it a permanent silky lustre. Dyeing is not only an art, it is also a branch of applied chemistry. One fundamental principle is, that the colouring matter and other necessary substances must be applied in a state of solution, and while in direct contact with the fibre they must be rendered insoluble, so that they are precipitated within or upon the fibre and fixed permanently. The method of effecting this varies greatly, according to the fibre and the colouring matter employed. As a rule, the vegetable and the animal fibres are dyed by very different methods. The affinity of the animal fibres for certain colouring matters is often so great that they are readily dyed by simple immersion in hot colour solutions; but this simple process is not generally sufficient. According to the method of their application in dyeing, the following groups of dye-stuffs may be distinguished:Acid Dyes,Basic Dyes,Direct Dyes,Developed Dyes,Mordant Dyes,Vat Dyes. A dye issubstantiveto a particular fibre when it dyes that fibre directly, andadjectivewhen the presence of a third substance known as amordantis necessary.
Theacid dyesare so called because they are of an acid character and are applied in an acid dye-bath. As a rule, they are only suitable for dyeing the animal fibres, e.g. wool and silk, also leather, horn, feathers, &c., and they are substantive to these materials. The purple vegetable dyestufforchilbelongs to this class. The acid dyes derived from coal-tar are very numerous, and yield a great variety of hues—red, orange, yellow, green, blue, violet, brown, and black. Thebasic dyesare so called because their essential constituents, to which they owe their dyeing power, are organic bases. The bases themselves are colourless and too insoluble in water to be of use, hence they are employed in the form of their soluble coloured salts, usually the hydrochlorides of the colour-bases. Their solutions are precipitated by tannic acid, because it combines with the colour-bases to form insoluble tannates. Wool, silk, and animal substances generally have a direct attraction for colour-bases, and hence these fibres are readily dyed by simple immersion in hot aqueous solutions of the basic dyes. Cotton and linen, on the other hand, are not dyed so readily; they need first to be mordanted or impregnated with themordanttannic acid. Most of the colours of this class are fugitive to light, and all but one, viz.barberry root, are derived from coal-tar products.
Thedirect dyesare so called because they dye cotton without the aid of any mordanting process. The first of this class derived from coal-tar wascongo red, discovered in 1884; at present this group includes a very great variety of fast colours, and forms, indeed, one of the most important and valuable series of dye-stuffs employed. Cotton, linen, and the vegetable fibres generally are dyed in the simplest possible manner by merely boiling them in a solution of the dye-stuff, with or without the addition of a little soap, carbonate or sulphate of soda, &c. Wool and silk are frequently dyed in the same manner as cotton. Very few vegetable dye-stuffs belong to the direct colours, e.g.Safflower,Turmeric,Saffron,Annatto(see the articles). They are all fugitive, and are now of little or no importance to the dyer. The coal-tar colours of this class, on the other hand, are extremely numerous. Thedeveloped dyesare formedin situupon the fibre by the successive application of two or more substances. They includeaniline black, a permanent black produced by the oxidation of aniline, and theice colours, which areazo dyesderived from certain coal-tar products containing nitrogen.
Themordant dyesform one of the most important classes of colouring matters, for they include not only most of the vegetable dye-stuffs, e.g. madder, logwood, fustic, &c., but also many valuable fast coal-tar colours, commonly known as thealizarin dyes, after their typical representative, alizarin. These mordant dyes have by themselves very little colouring power, as a rule, and if employed alone in dyeing give little or no result. If applied, however, in conjunction with metallic salts, notably those of chromium, aluminium, iron, tin, and copper, they each yield a variety of colours, according to the metallic salt employed. In employing them two distinct operations are usually involved: first, that of applying the metallic salt ormordant, called themordanting process; and second, that ofdyeingproper, in which the mordanted material is boiled in a solution or decoction of the dye-stuff. During the dyeing operation the colouring principle of the dye-stuff combines with the metallic salt already upon the material, and the colour is thus produced and fixed upon the fibre. The method of mordanting varies with the fibre and the metallic salt employed. The vegetable dye-stuffs of this class includeMadder,Sapanwood,Camwood,Barwood,Old Fustic,Young Fustic,Quercitron Bark,Persian Berries,Weld,Logwood(see these separate articles).Madderwas formerly the most important and highly valued of the dye-stuffs of this class, being especially employed to produce the fine 'Turkey-red' dye; but it is now entirely superseded by the coal-tar colour alizarin. Similarly, the employment ofcochineal(an insect dye) has also greatly diminished through the introduction of the cheaper colours.Camwoodandbarwoodare almost entirely used in wool-dyeing, either inconjunction with the indigo-vat or for the purpose of dyeing various shades of brown.Old fusticis the most important of the yellow mordant dye-stuffs, and the colours are fast although not very brilliant.Quercitron barkis an excellent dye-stuff employed by wool-dyers for the production of bright orange and yellow colours.Persian berriesandweld, a species of wild mignonette, are both excellent dye-stuffs, but their employment is now limited.Logwoodis largely employed by wool, silk, and cotton dyers for dyeing black and dark-blues, which, although fast to washing, are only moderately so towards light. The important vegetable dyecatechu(q.v.) is used in dyeing cotton and wool brown. On wool, catechu yieldskhakibrowns in single bath by using copper sulphate as the mordant. On silk, it is largely employed for weighting purposes in the process of dyeing black. Although dyewoods are still much employed, they are being steadily replaced by coal-tar colours. Thevat dyesare insoluble in water, but yield reduction products which are soluble in aqueous alkali, and can be readily reoxidized to the dye-stuff. In this class may be included thesulphur dyes, substances of uncertain composition obtained by fusing certain compounds containing nitrogen with sulphur and sodium sulphide, which are now extensively and increasingly employed, especially as direct dyes for cotton.Indigo, a typical vat dye, is prepared both artificially and from natural sources. It is a dark-blue powder quite insoluble in water, but when reduced it yieldsindigo-whitewhich dissolves in aqueous alkali, the solution thus obtained being called anindigo-vat. Cotton, wool, or silk steeped for some time in the clear yellow solution of such a vat, and then exposed to the oxidizing influence of the air, is dyed a permanent blue. The indigo-white absorbed by the fibre loses its acquired hydrogen, and thus insoluble indigo-blue is regenerated within and upon the fibre.
In the classification adopted above, the followingmineral coloursemployed in cotton dyeing belong to the group of developed dyes, since they are formed on the fibre:chrome yellow, obtained by immersing cotton successively in solutions of acetate of lead and bichromate of potash;iron buff(oxide of iron), produced by the successive application of sulphate of iron and carbonate of soda;Prussian blue, developed by passing the buff-dyed cotton through an acidified solution of potassium ferrocyanide;manganese brown(oxide of manganese), deposited similarly to iron buff. The mineral colours are very useful for certain purposes, and are very fast to light.—Bibliography: Crookes,A Practical Handbook of Dyeing and Calico-printing; W. P. Dreaper,Chemistry and Physics of Dyeing; Knecht, Rawson, and Loewenthal,Manual of Dyeing; Rawson, Gardner, and Laycock,A Dictionary of Dyes, Mordants, &c.
Dyer, John, English poet, born in Carmarthenshire about 1700, died in 1758. Educated at Westminster School, he became a painter, but, not succeeding in that vocation, took orders and was appointed to a small living. In 1727 he published his poem ofGrongar Hill, in 1740The Ruins of Rome, and in 1757The Fleece, a didactic poem in five books.
Dyer's-broom, a European and now also N. American shrub (Genista tinctoria), formerly used with woad for dyeing green.
Dyer's-weed,Resēda Luteŏla, a British plant of the same genus as mignonette, otherwise calledYellow-weed,Weld, orWoad, nat. ord. Resedaceæ. This plant grows in waste ground; it affords a beautiful yellow dye, and is cultivated for that purpose.—Dyer's GreenweedisGenista tinctoria.
Dying Declaration, a deposition made by one who is in prospect of death. Such declarations are as a general rule admissible as evidence only in criminal and not in civil cases, and must be made, according to English, though not Scottish law, in the full consciousness of the danger of death.
Dynam´icsis the science which deals with the laws of force in their relation to matter at rest or in motion, and as such it is differentiated fromkinematics, which considers motion mathematically, and apart from the forces producing it. Dynamics is divided into two great branches:statics, which treats of solid bodies at rest under the action of forces; andkinetics, which treats of the action of forces in producing motion in solid bodies. Formerly the latter alone was called dynamics, and to this, in conjunction with statics, the general namemechanicswas given. In the wide sense dynamics includes also hydrodynamics. It is to Newton that we owe the clear statement of the three primary laws of force on which the science of dynamics is based. These are: (1) that every body remains in a state of rest, or of uniform motion along a straight line, unless it is compelled by force to change that state; (2) that rate of change of momentum is in proportion to the force employed, and occurs along the straight line in which the force acts; (3) that, as the result of every action, there is always an equal and opposite reaction. These laws, which were formulated from experiment, involve the conception of force as a primary influence or action expressed in terms of space, time, and matter. Now, in dealing with the laws of force, a standard of measurement is required which shall be applicable to all forces at all times, and we therefore require to begin by establishing units of space, time, and mass. There are two systems of units in use, the one British, the other French. In the British systemthe foot is taken as the unit of length, and the second as the unit of time. In the French the centimetre is the unit of length, the second the unit of time; the unit velocity in the one case being that of one foot per second, in the other one centimetre per second. The British unit of mass is the pound (the mass of a certain lump of platinum deposited in the Exchequer Office, London); the French the gramme; and accordingly the French units of space, mass, and time are commonly known as the C.G.S. (centimetre, gramme, second) units. As the weight of a pound (or a gramme) is not the same at all parts of the earth's surface, it cannot give us of itself an absolute or dynamical unit of force, that is, an invariable unit; but taking it in conjunction with unit time and unit velocity, we do obtain such a unit. Two absolute units of force are in common use in dynamics, thepoundaland thedyne, the latter being the absolute unit in the C.G.S. system. The former isthat force which, acting on the mass of one pound for one second, generates in that mass a velocity of one foot per second. The latter isthat force which, acting on the mass of one gramme for one second, generates in that mass a velocity of one centimetre per second. It is important in dynamics to distinguish betweenmassandweight. Themassof one pound is the quantity of matter equal to a certain standard quantity (a certain lump of metal) and is quite independent of force. Theweightof one pound is the force with which the mass of one pound is attracted to the earth's surface by the force of gravity. Another important term ismomentum: the momentum of a body in motion at any instant is the product of the mass of the body and the velocity at that instant. SeeCouple;Elasticity;Energy;Force;Hydrodynamics;Kinematics;Kinetics;Statics;Thermodynamics;Waves.—Bibliography: Kelvin and Tait,Natural Philosophy; A. Gray,Dynamics; P. G. Tait,Dynamics; S. L. Loney,Mechanics and Hydrostatics for Beginners.
Dyn´amite.SeeExplosives.
Dy´namo.SeeGenerator.
Dynamom´eter, an apparatus for measuring the power or rate of working of a machine. There are two types, the transmission dynamometer, which measures the power of the machine without sensibly diminishing it; and the absorption dynamometer, which measures the power by using it all. The instrument is generally employed to determine the horse-power transmitted by a shaft or by belting.—Cf. Aspinall Parr'sElectrical Engineering Testing.
Dyrrhachium.SeeDurazzo.
Dy´sart, a royal and municipal burgh of Scotland, in Fife, on the Firth of Forth. It is an old place, and is a member of the Kirkcaldy district of parliamentary burghs. Pop. of royal burgh, 4197.
Dys´enteryis a disease of an acute type, due to the action of a bacillus, characterized by pain and frequent passage of blood and mucus. Owing to improved sanitation, dysentery has become less frequent. In temperate countries sporadic cases occur from time to time, and occasional epidemics break out, but in the tropics widespread epidemics occur, and the disease is a serious menace. It is a very frequent camp disease, and has been the scourge of all armies in tropical and semi-tropical regions. The bacilli are widely spread by the fæces of infected persons, and usually the infection takes place by the mouth. The onset is rapid, and marked by fever, pain in the abdomen, and frequent stools. At first mucus only is seen in the stools, but soon blood appears. In very acute cases the patient is seriously ill in forty-eight hours, and may die on the third or fourth day. Moderate cases may go on for several weeks, with resulting convalescence. Some cases become chronic in type, and a person may have chronic dysentery for years. Bismuth in large doses is given, and morphia is a most useful drug to relieve the pain and quieten the bowel. Normal saline solution is given by rectum after the acute stage, whenever possible. Chronic dysentery requires dietetic treatment for the persistent dyspepsia and irritability of the bowel. Amœbic dysentery, due to theAmœba dysenteriæ, is a distinct disease.
Dys´odile, a yellowish or greenish foliated carbonaceous substance found in Sicily originally, and derived from the decay of minute organisms. When ignited, it burns and emits a very unpleasant smell.
Dyson, Sir Frank Watson,F.R.S.,LL.D.(Edin.), British astronomer, born at Ashby 8th Jan., 1868, the son of a Baptist minister. Educated at Bradford Grammar School and Trinity College, Cambridge, he became chief assistant at the Royal Observatory, Greenwich, in 1894, and secretary of the Royal Astronomical Society in 1899. Astronomer Royal for Scotland in 1905, he was appointed Astronomer Royal for England in 1910. He was knighted in 1915.
Dyspep´sia, orGastritis, may be either acute or chronic.Acute dyspepsiamay follow when more food is taken than the stomach can digest, or when unsuitable articles are taken. The symptoms are headache, depression, nausea, vomiting, with pain, varying from a feeling of discomfort in the abdomen to marked tenderness. The tongue is furred, and usually there is diarrhœa, while in the more severe attacks the onset is marked by chill and a rise of temperature. An attack may last from one day to four days. Treatment for mild cases is simply a dose of castor-oil (children) or blue pill (adults), but in severe cases vomiting should be promoted by warm water, or the stomach tube if necessary,and a dose of calomel (3 grains), followed by salts, should be given. Absolute rest to the stomach is necessary, and only small quantities of water allowed. Repeated attacks lead to the establishment of the chronic form.Chronic dyspepsiais a condition of disturbed digestion due to the prolonged use of unsuitable, or improperly prepared, foods. Hot cakes, excess of tea, coffee, or alcohol, rapid and irregular meals are all common causes. It may also arise in the course of diseases like anæmia, chronic tuberculosis, gout, Bright's disease, chronic heart disease, cirrhosis, and in diseases of the stomach itself, as cancer, gastric ulcer, and gastric dilatation. The most common symptoms are a feeling of oppression after food, tenderness over the stomach, headache, nausea, flatulence, constipation, and occasionally vomiting. Treatment consists of dietetic measures, regulated exercises, change of air and surroundings, and avoidance of depression. Milk should be used freely, and in severe cases should be given alone till improvement sets in. Fats and greasy dishes should be avoided. Fruits are sometimes well borne, and at other times the reverse. Drugs do not play so important a rôle, but bitter tonics, like nux vomica, quassia, gentian, &c., are the best. Constipation should be treated when necessary.
Dyspho´niais difficulty in speaking, and is the result of some forms of laryngitis. The condition is aggravated by attempts to use the voice, and complete rest is necessary to bring about an early and satisfactory recovery. Tonics, moderate exercise, and a holiday hasten recovery.
Dyspnœa(dis-pnē´a) is difficult or laboured breathing. It is a symptom of diseases of the heart or lungs, and is produced by any condition which interferes with normal respiration. It is sometimes present in nervous disturbances.
Dze´ren, orDze´ron, the Chinese antelope, a remarkably swift species of antelope (Procapra gutturōsa) inhabiting the dry arid deserts of Central Asia, Tibet, China, and Southern Siberia. It is nearly 4½ feet in length, and 2½ feet high at the shoulder.
Dzig´getai, orKiang(Equus hemiŏnus), a species of wild ass native to Central Asia, allied both to the horse and ass. Its head is large like that of the ass, but in form resembles that of the horse. The ears also resemble those of the horse. It runs with a rapidity exceeding that of the best Arabian horses.
Dzoungaria, orSungaria, a Chinese territory in Central Asia, stretching from about 43° to 48°N.lat. and from about 82° to 86°E.long. It has an area of 147,950 sq. miles, and pop. 600,000. It is administratively connected with Kuldja, and since the surrender of Kuldja by the Russians in 1880 is again under Chinese rule. Dzoungaria, once the centre of an independent empire, was first conquered by the Chinese in 1757.
E, the second vowel and the fifth letter of the English alphabet. It occurs more frequently in English words than any other letter of the alphabet. Its long or natural sound in English coincides with the sound ofiin the Italian and French languages, as inhere,mere,me. It has also another principal sound, a short one, heard inmet,men. It has besides a sound likeainbare, as inthere,where, &c., and the obscure sound which is heard inher. As a final letter in English it is generally silent, but it serves to indicate that the preceding vowel is to have its long sound, as inmane,cane,plume. When twoe's come together the sound is generally the same as that of the singleelong, as indeem,esteem,need(compare, however,pre-exist, &c.).
E, in music, is the third note or degree of the diatonic scale, answering to themiof the Italians and French.
Eadie(ē´di), John,D.D., a Scottish preacher and theologian, born 1810, died 1876. He was educated at Glasgow University, and entered the ministry of the Secession Church, becoming in 1843 professor of biblical literature in the Divinity Hall of the Church, a post which he continued to hold after the Secession body was merged in the United Presbyterian Church (in 1847). Among his works areBiblical Cyclopædia;Analytical Concordance to the Scriptures;Ecclesiastical Cyclopædia;Commentary on the Greek Text of Ephesians, and similar works onColossians,Philippians, andGalatians; andThe English Bible. He was one of the scholars engaged on the Revised Version of the New Testament.
Ead´mer, an English monk, the friend and biographer of St. Anselm. In 1120 he was chosen Bishop of St. Andrews; but as the Scottish king refused to recognize the right of the Archbishop of Canterbury to consecrate him, he returned to England and died a simple monk about 1124. Besides the life of St. Anselm, Eadmer wrote lives of St. Wilfrid, St. Dunstan, St. Odo, and other English saints, as well as a valuable history (Historiæ Novorum) of events in England and the English Church from 1066 to 1122.