at Edinburgh, 1859, studied medicine, and for some years practised, but
gave up the profession for that of literature. In 1887 he produced _A Study
in Scarlet_, in which he created the detective Sherlock Holmes. Among his
other books are: _Micah Clarke_, _The Sign of Four_, _The White Company_,
_The Adventures of Sherlock Holmes_, _Brigadier Gerard_, _The Great Boer
War_, _The Crime of the Congo_, _The Lost World_, _The Poison Belt_, _The
British Campaign in France and Flanders_, _The New Revelation_, and _The
Vital Message_.
DOYLE, Sir Francis Hastings Charles, English poet, born 21st Aug., 1810,
died 8th June, 1888, was the son of Major-General Sir Francis Hastings
Doyle, first baronet, succeeding his father in the title in 1839. Educated
at Eton and Oxford, he graduated with first-class honours in classics in
1832, and held a fellowship at All Souls' from 1835 to 1844. After some
years' work as a barrister, he became Receiver-General, and in 1869
Commissioner of Customs, having two years previously been elected professor
of poetry at Oxford in succession to Matthew Arnold, a position to which he
was re-elected for a second term five years later. He had already published
_Miscellaneous Verses_ (1840); _The Two Destinies_ (1844); _The Return of
the Guards and other Poems_ (1866); and subsequently printed his _Oxford
Lectures_ (1869 and 1877) and _Reminiscences and Opinions, 1813-85_ (1886).
DOYLE, Richard, an artist, born in London in 1824, died in 1883. He was
long well known as a constant contributor of satirical designs to _Punch_,
and also showed much talent in illustrations to Leigh Hunt's _Jar of
Honey_, Thackeray's _Newcomes_ and his _Rebecca and Rowena_, and Ruskin's
_King of the Golden River_. Afterwards he devoted himself to water-colour
painting.
DOZY (d[=o]'zi), Reinhart, Dutch Orientalist and historian, born 1820, died
1883. He was thoroughly versed in most of the Semitic tongues, and spoke
and wrote almost all the European languages with facility. Among his works
(sometimes in Dutch, sometimes in French) are: _Histoire des Musulmans
d'Espagne de 711-1110_, _G['e]ographie d'Edrisi_, _De Israelieten te
Mekka_, _Het Islamisme_], _Supplements aux Dictionnaires Arabes_.
DRAA, or WADY DRAA, a river, or rather water-course, of Morocco, rising in
the Atlas Mountains and flowing generally south-east, until, after
penetrating the Anti-Atlas range and passing several oases, it suddenly
turns westwards, and forms the shallow lagoon El Debaia. From this point
until it enters the ocean it is a wady, and forms the southern boundary of
Morocco.
DRACAE'NA, a genus of endogenous evergreen plants, nat. ord. Liliaceae. It
includes the dragon tree of Teneriffe (_D. Draco_), celebrated for
producing the resin called dragon's blood. Several species of Dracaena are
cultivated in greenhouses for the beauty of their foliage, but many of the
fine plants known by this name belong strictly to other genera.
DRACHENFELS (dr[:a]'_h_en-fels; 'dragon rock'), "the castled crag of
Drachenfels", as Byron calls it, a hill in Rhenish Prussia, about 8 miles
south-east of Bonn, rising 900 feet above the Rhine, and crowned by the old
castle of Drachenfels.
DRACHMA (drak'ma), the unit of weight and of money among the ancient
Greeks. It was the principal Greek coin, was made of silver, and was worth
(the Attic drachma) about 9-3/4d. As a weight amongst the Greeks it was
about 2 dwt. 7 grains troy. The monetary unit of modern Greece is also
called a drachma. Since 1867 its value has been equivalent to that of the
franc of the Latin Monetary Union. It is divided into 100 _lepta_.
DRACO, a legislator of Athens, about 620 B.C., whose name has become
proverbial as an inexorable and bloodthirsty lawgiver, and whose laws were
said to have been written in blood, not ink. Suidas says that he met his
death at Aegina, being unintentionally suffocated by the caps and cloaks
thrown at him by some of his enthusiastic supporters.
DRACO, the Dragon, a constellation of the northern hemisphere, consisting
of a long and straggling line of stars, coiled about Ursa Minor, the Lesser
Bear. The Pole of the Ecliptic, or earth's orbital plane, is in this
constellation, and round that point the Pole of the Equator, at present
close to [alpha] Ursae Minoris (the 'Pole Star'), travels in a circle in
about 26,000 years. Some 4000 years ago [alpha] Draconis was pole-star.
DRAG, (1) a long coach or carriage, generally uncovered and seated round
the sides; (2) an apparatus for retarding or stopping the rotation of one
wheel or of several wheels, in carriages especially; (3) an apparatus,
consisting of a frame of iron with a bag-net attached, used to recover
articles lost in the water.
DRAG-NET, a net drawn along the bottom of a river or pond to catch fish.
The use of drag-nets is usually prohibited in rivers where fish breed, as
it takes all indiscriminately.
DRAGO DOCTRINE, a doctrine formulated by L. M. Drago, an Argentinian jurist
and Minister for Foreign Affairs, and asserting the principle that no power
had a right to impose itself by force of arms upon any of the Spanish
American nationalities. Drago first advanced his doctrine in 1902, when the
British, German, and Italian fleets were blockading the Venezuelan coast to
compel President Castro to pay certain claims made upon his government.
DRAGOMIROV, Mikhail Ivanovitch, Russian general, born in 1830, died in
1905. He became known as lecturer on military tactics, and was appointed
chief of the Russian general staff at Kiev. During the Russo-Turkish War he
distinguished himself at the crossing of the Danube at Sistova, and was
wounded at the Shipka Pass. Retired from active service, he was director of
the War Academy at St. Petersburg, Governor-General of Kiev from 1898 to
1902, and member of the Council of the Empire. His works include: _The
Austro-Prussian War_, _A Study on the Novel 'War and Peace'_, _The French
Soldier_, _War is an Inevitable Evil_, and _Duels_.
DRAGOMIROV, Vladimir, son of the former, was prominent as a commander
during the European War, and took part in the offensive in Galicia in 1916.
In 1919 he was president of General Denikin's Political Council, and
Governor of Kiev.
DRAGON (Gr. _drakon_, 'the seeing one', a serpent). This 'composite wonder
beast' is prominent not only in fairy lore and mediaeval romances, but in
ancient religious systems. In the mythical history of the East the dragon
is the symbol of anarchy and destruction, and the idea was taken over by
Christianity, which looked upon the dragon as an emblem of the devil. In
Ancient Egypt certain of the deities had serpentine forms, as have still
some of the dragons of India, China, and Japan. The Egyptian 'fiery flying
serpent' is a dragon, as is also the Apep serpent of night and death,
through which the sun-barque of Ra was supposed to pass each night.
Biblical references to it as the 'worm' include: "Their worm shall not die"
(_Is._ lxvi, 24); "The worm shall eat them like wool" (_Is._ li, 8); "In
that day the Lord, with his sore, and great, and strong sword, shall punish
leviathan the piercing serpent," &c. (_Is._ xxvii, 1); "The great dragon
was cast out, that old serpent, he that is called the Devil and Satan"
(_Rev._ xii, 9). See also _Ps._ lxxxvii, 4, and lxxxix, 10; _Amos_, ix, 3;
and _Is._ li, 9. Osiris, as the Nile, was a dragon on which were human
heads. In the Pyramid Texts he is addressed as "the Great Green" (the
Mediterranean Sea), and the one who is "round as the Great Circle
(Okeanos)." On the sarcophagus of Seti I he is "Osiris encircling the
Nether World." Set, who slew him, had a 'roaring serpent' form and hid in a
hole; he resembled Typhon. The Babylonian dragon Tiamat was the Great
Mother of all the deities, and was slain by her descendant Marduk
(Merodach), who formed the earth and sky from her body; her blood ran as
the flooded rivers to the sea. In India the drought-demon is a water
confiner. When slain by Indra with the thunderbolt, the rainy season
ensues. The Naga serpent-gods are dragons who may assume human or
half-human, half-reptile forms. They guard treasure and chiefly pearls.
Early pearl-fishers believed that the shark was the owner and guardian of
pearls. Among the Chinese dragons is the lion-headed shark. All the Chinese
dragons have pearls in their mouths, and are supposed to spit out pearls.
Dragon deities are connected with the moon, which is 'the night-shining
pearl,' and in Mexico 'the pearl of heaven'. The Mexican dragon resembles
the Chinese, Indian, and Babylonian dragons. The Indian wonder-beast, the
_Makara_, the vehicle of the sea-god Varuna, is similar to the dragon of
the Babylonian mother-goddess Ishtar seen on the famous Ishtar gate of
Babylon. _Makara_ forms include the lion-headed dolphin, the
crocodile-headed fish, and the ram-headed fish so like the 'goat fish' or
'antelope fish' of the Babylonian sea-god Ea, and resembling the Greek
horse-headed, dog-headed, and man-headed fish (Tritons). Japanese dragons
are serpentine 'water fathers', which are prayed to in time of drought. The
Chinese dragons are rain-bringers which sleep during the winter (the season
of drought) in pools and rise to fight and thunder in spring. They are
hatched from stones as snakes, or from sea-plants, or are transformed fish,
or are born from aged pine trees. They are coloured according to their
attributes, and may assume human forms or be horse-headed with a snake's
tail. That the composite dragon-god is a mixture of several ancient
animal-gods is evident by the following description of one class of dragon
by a Chinese writer: "His horns resemble those of a stag, his head that of
a camel, his eyes those of a demon, his neck that of a snake, his belly
that of a clam, his scales those of a carp, his claws those of an eagle,
his soles those of a tiger, his ears those of a cow." Dragons may transform
themselves into fishes, snakes, crows, dogs, rats, cows, sharks, whales,
crocodiles, &c., as well as human beings. The 'will o' wisp' is the 'dragon
lantern', and the dragon pearl is the 'jewel that grants all desires' in
India, China, and Japan. Dragon herbs cure diseases and prolong life.
Dragons carry souls to the Celestial regions, or draw vehicles in which
souls stand. This Far Eastern belief existed in Ancient Crete too. On a
Cretan sarcophagus is a chariot drawn by two griffins (forms of the dragon)
in which stands a woman, probably a goddess, and a swathed pale figure, the
deceased. Shakespeare has interesting dragon references, including:
The dragon wing of night o'erspreads the earth,...
(_Troilus and Cressida_, V, 8, 17.)
Swift, swift, you dragons of the night, that dawning
May bare the raven's eye.
(_Cymbeline_, ii, 2, 49.)
It is believed that the treasure-guarding dragon of the romances had origin
in mixed memories regarding the pearl-guarding shark, the fiery flying
serpent, and the ancient serpent and crocodile demons of destruction,
flood, darkness, and death. The whole idea of dragons may have originated
from traditions about the pterodactyls which lived in the Mesozoic period.
The dragon being a symbol of destruction and a power of evil, the slaying
of a dragon was considered a great achievement of mediaeval heroes, such as
King Arthur, Beowulf, Siegmund, and Tristram.--Cf. G. Elliot Smith, _The
Evolution of the Dragon_; M. W. de Visser, _The Dragon in China and Japan_.
[Illustration: Dragon-fly
A, Larva of dragon-fly. B, Dragon-fly escaping from chrysalis. C, The
perfect insect.]
DRAGON, or DRAGON-LIZARD, a name for several species of lizards inhabiting
South-East Asia. The common flying lizard (_Draco volans_), the best type
of the genus, is about 10 or 12 inches in length, the tail being extremely
long in proportion to the body. The sides are furnished with peculiar
extensions of the skin, resembling wings, which help to support it in the
air as it springs from branch to branch. These wing-like processes are
borne by prolongations of five or six of the hindermost ribs, and can be
folded up. Its food consists almost exclusively of insects.
DRAG'ONET, the common name of small marine fishes constituting a special
family (Callionymidae). The gemmeous dragonet (_Callionymus lyra_) is found
in the British seas. The female is dull brown and much smaller than the
male, which is brilliantly coloured with spots and bars of blue on a yellow
ground. His first dorsal fin is large and drawn out into a long filament.
DRAGON-FLY, the common name of members of a family (Odonata or
Libellulidae) of neuropterous insects. They have a large head, large eyes,
and strong horny mandibles. They are beautiful in form and colour, and are
of very powerful flight. The great dragon-fly (_Aeschna grandis_) is about
4 inches long, and the largest of the British species. They live on
insects, and are remarkable for their voracity. The dragon-fly deposits its
eggs in the water, where the wingless nymphs live on aquatic insects. The
nymph stage lasts for a year. The family is of very wide distribution. The
small blue Agrion is a common European form, but the familiar Libellula is
the most extensively distributed. See _Demoiselle_.
DRAGONNADES, or DRAGONADES, the name given to the persecutions directed
against the Protestants, chiefly in the south of France, during the reign
of Louis XIV, shortly before the revocation of the Edict of Nantes in 1685.
Bands of soldiers, headed by priests, marched through the villages, giving
the Protestant inhabitants the alternative of renouncing their faith or
being given over to the extortions and violence of the soldiery. The
dragoons were conspicuous in these expeditions, to which they gave their
name. The Dragonnades drove thousands of French Protestants out of
France.--Cf. Tylor, _The Huguenots in the Seventeenth Century._
DRAGON'S BLOOD, or GUM DRAGON, a resinous juice, usually obtained by
incision from various tropical plants, as _Cal[)a]mus Draco_, _Dracaena
Draco_, _Pterocarpus Draco_, &c. It varies in composition, and is often
much adulterated. It is opaque, of a reddish-brown colour, brittle, and has
a smooth shining conchoidal fracture. It is soluble in alcohol and oil, but
scarcely so in water. It is used for colouring varnishes, for staining
marble, leather, and wood, and for tooth tinctures.
[Illustration: Dragon Tree (_Dracaena Draco_)
1, Fruiting branchlet. 2, Flowers.]
DRAGON TREE (_Dracaena Draco_), a tree-like liliaceous plant, with a stem
simple or divided at top, and in old age often much branched. It is a
native of the Canaries, and yields the resin known as dragon's blood. It is
often grown in greenhouses.
DRAGOON', a kind of mounted soldier, so called originally from his musket
(_dragon_) having on the muzzle of it the head of a dragon. At one time
dragoons served both as mounted and foot soldiers, but now only as the
former. In the British army there are _heavy_ and _light dragoons_. The
first dragoon regiment, the Scots Greys, was formed in 1681.
DRAGUIGNAN (dr[.a]-g[=e]-ny[:a]n),a town of Southern France since 1793,
capital of the department of Var, in a beautiful valley, 41 miles
north-east of Toulon. It has some interesting buildings, and manufactures
of silk, soap, and leather. Pop. 9974.
DRAINAGE. The term comprises the drainage of areas of country by rivers and
streams, the reclamation of areas from the sea, and country formerly
marshy, and the provision of culverts and pipe-drains to buildings and
towns.
The Fens in Lincolnshire are a notable example of a comprehensive system of
drainage by means of open ditches (locally called 'drains'), into which the
surplus water is lifted by means of wind- and steam-pumps.
Low-lying or flat country often requires a considerable amount of drainage,
which is carried out by means of a regular system of earthenware pipes,
laid 2 to 3 feet deep, and from 15 to 35 feet apart. These pipes are
porous, from 2 to 3 inches in diameter, laid with butt joints, and lead
into larger mains, and thence by open ditches to streams.
A method recently introduced consists in drawing a pointed cylindrical
tool, 2 inches in diameter, through the ground at the required depth. This
tool is dependent from a thin steel plate, which connects it with the
carriage above, so that it can be drawn underground in any desired
direction. This system is economical in first cost, but its useful life is
considerably less than that of a piped drain, and its use is obviously
confined to soils of the heavier variety.
In considering the provision of drainage to water-logged or low-lying land,
every care should first be taken to improve the existing natural means of
drainage, such as deepening and cleaning out streams and ditches, and
removing obstructions.
It should be borne in mind that the object of land drainage is not only to
remove the surplus water, but to promote a free and natural circulation of
water in the soil, and to allow the mineral constituents of the water to
reach the plant roots.
In the drainage of buildings, glazed socketed stoneware pipes are used,
varying in diameter from 3 to 9 inches, laid straight in plan and in
longitudinal section, and laid to falls, calculated to give a minimum
velocity of 3 feet per second when flowing half full. These are laid in
trenches, with inspection chambers at all changes in direction, and should
be laid on and surrounded with concrete. In bad ground, or under dwelling
houses, cast-iron pipes are employed, with special turned and bored joints.
In towns these drains lead into the public sewers, which are similar
stoneware pipes from 6 to 18 inches in diameter, larger sizes being
constructed in brickwork or concrete, and either circular or egg-shaped
form. In populous areas these sewers attain very large dimensions, the
northern outfall sewers of London consisting of five parallel sewers, each
9 feet in diameter. See _Draining_.--BIBLIOGRAPHY: G. S. Mitchell,
_Handbook of Land Drainage_; Moore and Silcock, _Sanitary Engineering_;
Gilbert Thomson, _Modern Sanitary Engineering_.
DRAINAGE TUBES are fenestrated india-rubber tubes used in surgery to effect
the gradual removal of the contents of a suppurating cavity. The inner end
of the tube is in the cavity, and the outer end projects above the skin
surface, and is usually fixed by a stitch or safety-pin, and covered with
suitable dressings.
[Illustration: Covered Drain without Pipes]
[Illustration: Open Drain]
[Illustration: Stone-laid Drains]
DRAINING, in agriculture, a method of improving the soil by withdrawing the
superfluous water from it by means of channels that are generally covered
over. Plants cannot thrive unless there is free circulation of air and
water round their roots. The successful practice of draining in a great
measure depends on a proper knowledge of the superficial strata, of their
situation, relative degrees of porosity, &c. Some strata allow water to
pass through them, while others more impervious force it to run or filtrate
along their surfaces till it reaches more level ground below. In general,
where the grounds are in a great measure flat and the soils of materials
which retain the excess of moisture, they require artificial means of
drainage to render them capable of yielding good crops whether of grain or
grass. The wetness of land, which makes it inferior for agricultural
purposes, may appear not only as surface-water but as water which flows
through the lower strata, and to draw off these there are the two distinct
operations of surface-draining and under-draining. The rudest form of open
drains are the deep furrows lying between high-backed ridges, and meant to
carry off the surplus water after the soil is completely saturated, but in
doing so they generally carry off also much of the best of the soil and of
the manure which has been spread upon it. The ordinary ditch is a common
form of water-course useful in certain cases, as in hill pastures. But
covered drains at a depth of 4 feet or so are the common forms in draining
agricultural lands. They are generally either _stone-drains_ or
_tile-drains_. Stone-drains are either formed on the plan of open culverts
of various forms, or of small stones in sufficient quantity to permit a
free and speedy filtration of the water through them. The box-drain, for
instance, is formed of flat stones neatly arranged in the bottom of the
trench, the whole forming an open tube. In tile-drains, tiles or pipes of
burnt clay are used for forming the conduits. They possess all the
qualities which are required in the formation of drains, affording a free
ingress to water, while they effectually exclude earth, as well as other
injurious substances, and vermin. Drainage tiles and pipes have been made
in a great variety of forms, the earliest of which, since the introduction
of thorough draining, was the horse-shoe tile, so called from its shape.
These should always rest on soles, or flats of burned clay. Pipe tiles,
which combine the sole and cover in one piece, have been made of various
shapes, but the best form appears to be the cylinder. An important
department of draining is the draining off of the waters which are the
sources of springs. The judicious application of a few simple drains, made
to communicate with the watery layers, will often dry swamps of great
extent, where large sums of money, expended in forming open drains in the
swamp itself, would leave it but little improved. In the laying out of
drains the first point to be determined is the place of outfall, which
should always afford a free and clear outlet to the drains, and must
necessarily be at the lowest point of the land to be drained. The next
point to be determined is the position of the minor drains. In the laying
out of these the surface of each field must be regarded as being made up of
one or more planes, as the case may be, for each of which the drains should
be laid out separately. Level lines are to be set out a little below the
upper edge of each of these planes, and the drains must then be made to
cross these lines at right angles. By this means the drains will run in the
line of the greatest slope, no matter how distorted the surface of the
field may be. All the minor drains should be made to discharge obliquely
into mains or submains, and not directly into an open ditch or
water-course. As a general rule, there should be a main to receive the
waters of the minor drains from every 5 acres. The advantages of drainage
are obvious. In the first place it brings the soil into a more suitable
condition for the growth of plants, aiding in producing the finely divided
and porous state which allows the roots and rootlets to spread themselves
at will in order to obtain the needed supplies of food, air, and moisture.
It also allows the sun's rays to produce their full effect on the soil and
plants. In the presence of stagnant water a great part of this effect would
be lost. See _Drainage_.
[Illustration: Horse-shoe and Cylindrical Drain Tiles]
[Illustration: Drain-traps]
DRAIN-TRAP, a contrivance to prevent the escape of foul air from drains,
while allowing the passage of water into them. They are of various forms.
In the traps represented below it will be seen that there must always be a
certain quantity of water maintained to bar the way against the escape of
the gas from the drain or sewer. When additional liquid is conveyed to the
trap, there is, of course, an overflow into the drain. In older types of
drains the gas was prevented from escaping by a metal plate thrown
obliquely over the drain mouth and dipping into the water in the vessel
beyond it.