rubberized cotton-fabric gas-container (the 'envelope'), from which the
'car', containing engines, crew, &c., is hung by flexible steel-wire ropes.
To resist the bending moment introduced by the weight of the car, the
envelope is inflated with hydrogen under pressure--usually about 25 mm. of
water. So long as this pressure is greater than any local compression due
to bending or loading in the fabric, the envelope will retain its shape. On
coming down from a height, owing to the loss of gas, as already explained,
the pressure will be reduced, and something must be done to restore it or
the envelope will buckle. Fabric bags, known as 'ballonets', are therefore
fitted inside the envelope, and as the air-ship descends air is forced into
these bags, which supplies the lost pressure and maintains the shape of the
envelope. The height to which a non-rigid air-ship can go, on returning
from which the ballonets will be just full of air and the pressure the same
as at starting, is known as the 'maximum ballonet height'. Ballonets are
usually equivalent in volume to rather less than a quarter of the total
volume of the air-ship--giving a maximum ballonet height of 6000 to 7000
feet. Usually from two to three ballonets are provided, according to the
size of the air-ship. During the Great European War British non-rigid
air-ships were constructed varying in size from a capacity of 70,000 cu.
feet to 360,000 cu. feet. The former had one 75-h.p. engine, and the latter
two of 375 h.p. each. Owing to difficulties in maintaining the shape and
distributing the weight of the car over a long envelope, it is generally
considered that 500,000 cu. feet probably represents the maximum size in
which the non-rigid form of construction can be used. Above this size the
_semi-rigid_ type is used. In this case the envelope remains as in the
non-rigid, but a girder or 'keel' is introduced between the envelope and
the car, the weight of which is therefore taken by the keel and thence
distributed to the envelope instead of being taken direct from the envelope
as in non-rigids. There has been little development of non-rigids in Great
Britain. The most prominent types are the Italian 'Forlanini', 'Verduzzio',
and military air-ships. The keel, in all these examples, is not a rigid
girder in the vertical sense, as it consists of a number of sections
connected together by links. It is designed to resist compression only so
long as it is held straight by the pressure of the envelope, and is not
capable of taking a bending moment. When a size of about
1,000,000-cu.-foot-hydrogen capacity is reached it becomes economical to
use the _rigid_ method of construction. This is totally distinct from the
other two types, as the non-rigid envelope is replaced by a rigid hull of
sufficient strength to retain its shape without the assistance of any
internal gas-pressure. The hull consists of a number of longitudinal
members--usually built-up girders of 'duralumin', an aluminium
alloy--connected together at distances of 25-30 feet by a number of
'transverse frames', or rings, forming bulkheads. The transverse frames are
also of duralumin girders, and are braced by 'radical wires' running from
the joints of these girders to a ring in the centre. Between each pair of
these transverse frames is a gas-bag containing hydrogen. The gas-bags are
made of rubberized cotton on to which is stuck 'gold-beater's skin', made
from the lining of the intestines of an ox. This is done to prevent
hydrogen leakage. This is necessary, as the fabric of the gas-bags of a
rigid air-ship is lighter and contains less rubber than the envelope of a
non-rigid.
A '[Delta]'-shaped keel runs along the interior of the ship, its weight
being taken on the two bottom longitudinal girders. The chief function of
the keel is to distribute the load of the various weights to the transverse
frames of the air-ship. In it are slung the petrol-tanks, water-ballast
tanks, bombs, &c., and living accommodation for the crew is also provided
there. Along the bottom runs a walking-way from which access is gained to
the cars and various parts of the air-ship. The cars containing the
engines, wireless-cabin, and pilot's cabin are suspended from the
transverse frames. Some of the cars, instead of being slung below the
centre-line, are slung in pairs some little way up the side of the
air-ship.
All air-ships are steered by means of rudders and, in the vertical sense,
elevators, in precisely the same way as aeroplanes. Up to the end of 1919
speeds of 84 miles per hour had been reached and air-ships had climbed to
24,000 feet. The greatest distance covered in one flight was 4500 miles,
while the longest time in the air was effected by R34 on her voyage to
America, which occupied 108 hours--4 days 8 hours. Rigid air-ships of
2,750,000-cu.-foot capacity had been built with a length of nearly 300 feet
and a gross lift of 60 tons. See also _Aeronautics_,
_Balloons_.--BIBLIOGRAPHY: L. Sazerac de Forges, _La Conquete de l'Air_;
Santos Dumont, _My Airships_; Hildebrandt, _Airships: Past and Present_;
Major G. Whale, _British Airships: Past, Present, and Future_.
AIRY, Sir George Biddell, a distinguished English astronomer, was born at
Alnwick, 27th July, 1801, and educated at Hereford, Colchester, and Trinity
College, Cambridge, where he was senior wrangler in 1823. At Cambridge he
was Lucasian professor of mathematics, and subsequently Plumian professor
of astronomy and experimental philosophy, in the latter capacity having
charge of the observatory. In 1835 he was appointed Astronomer Royal, and
as such his superintendence of the observatory at Greenwich was able and
successful. He resigned this post with a pension in 1881. His important
achievement is the discovery of a new inequality in the motions of Venus
and the earth. He wrote much and made numerous valuable investigations on
subjects connected with astronomy, physics, and mathematics. Among separate
works published by him may be mentioned _Popular Astronomy_, _On Sound and
Atmospheric Vibrations_, _A Treatise on Magnetism_, _On the Undulatory
Theory of Optics_, _On Gravitation_. He died 2nd Jan., 1892. He left an
autobiography, published in 1896.
AISLE ([=i]l; from Lat. _ala_, a wing), in architecture, one of the lateral
divisions of a church in the direction of its length, separated from the
central portion or nave by piers or pillars. There may be one aisle or more
on each side of the nave. The cathedrals at Chichester, Milan, and Amiens
have five aisles, Antwerp and Paris seven, and that of Cordova nineteen
aisles in all. The nave is sometimes called the central aisle. See
_Cathedral_.
AISNE ([=a]n), a north-eastern frontier department of France; area, 2838
sq. miles. It is an undulating, well-cultivated, and well-wooded region,
chiefly watered by the Oise in the north, its tributary the Aisne in the
centre, and the Marne in the south. It contains the important towns of St.
Quentin, Laon (the capital), Soissons, and Chateau Thierry. In the European
War (1914-18) severe fighting took place on the Aisne, and a great battle
was fought on 12th Sep., 1914. General Nivelle's offensive on the Aisne
began in April, 1917. Pop. (1921), 421,575.
AIVA'LIK, or KIDONIA, a seaport of Asia Minor, on the Gulf of Adramyti, 66
miles north by west of Smyrna, carrying on an extensive commerce in
olive-oil, soap, cotton, &c. Pop. 21,000.
AIX ([=a]ks), a town of Southern France, department Bouches-du-Rhone, on
the River Arc, the seat of an archbishop. It is well built, has an old
cathedral and other interesting buildings, including a university, a
library (over 100,000 vols.), museum, &c.; manufactures cotton and woollen
goods, oil, soap, hats, flour, &c.; warm springs, now less visited than
formerly. Aix was founded in 123 B.C. by the Roman consul Gaius Sextius
Calvinus, and from its mineral springs was called _Aquae Sextiae_ (Sextian
Waters). Between this town and Arles, Marius gained his great victory over
the Teutons, 102 B.C. In the Middle Ages the counts of Provence held their
court here, to which the troubadours used to resort. Pop. 29,836.
AIX, or AIX-LES-BAINS ([=a]ks-l[=a]-ba[n.]), a finely-situated village of
France, department of Savoie, 8 miles north of Chambery, on the side of a
fertile valley, with much-frequented hot springs known to the Romans by the
name of _Aquae Gratianae_, and with ruins of a Roman triumphal arch, and of
a temple of Diana. Pop. 8900.
AIX-LA-CHAPELLE ([=a]ks-l[.a]-sh[.a]-pel; Ger. _Aachen_), a city of Rhenish
Prussia, 38 miles west by south of Cologne, pleasantly situated in a fine
vale watered by the Wurm, formerly surrounded by ramparts, now converted
into pleasant promenades. It is well built, and though an ancient town has
now quite a modern appearance. The most important building is the
cathedral, the oldest portion of which, often called the nave, was erected
in the time of Charles the Great (Charlemagne) as the palace chapel about
796. It is in the Byzantine style, and consists of an octagon, surrounded
by a sixteen-sided gallery and surmounted by a cupola, in the middle being
the tomb of Charlemagne. The adjoining Gothic choir, begun in 1353 and
finished in 1413, forms the other chief division of the cathedral; it is
lofty and of great elegance, and has fine painted windows. Another
noteworthy building is the Rathaus (town hall), erected in the fourteenth
century. Aix-la-Chapelle, with the adjoining Burtscheid, which may be
considered a suburb, is a place of great commerce and manufacturing
industry, the chief productions being woollen yarns and cloths, needles,
machinery, cards (for the woollen manufacture), railway and other
carriages, cigars, chemicals, silk goods, hosiery, glass, soap, &c. A
considerable portion of its importance and prosperity arises from the
influx of visitors to its sulphur and chalybeate springs and
baths.--Aix-la-Chapelle was known to the Romans as _Aquisgranum_. It was
the favourite residence of Charles the Great, who made it the capital of
all his dominions north of the Alps, and who died here in 814. During the
Middle Ages it was a free imperial city and very flourishing. Thirty-seven
German emperors and eleven empresses have been crowned in it, and the
imperial insignia were preserved here till 1795, when they were carried to
Vienna. The town was in possession of France from 1794 to 1814. Pop.
156,143.--_Congress of Aix-la-Chapelle_, a congress held in 1818, by which
the army of the allies in France was withdrawn after France had paid the
contribution imposed at the peace of 1815, and by which independence was
restored to France.--A _treaty_ of peace concluded at this city, 2nd May,
1668, as a result of the Triple Alliance, put an end to the war carried on
against Spain by Louis XIV in 1667, after the death of his father-in-law,
Philip IV, in support of his claims to a great part of the Spanish
Netherlands, which he urged in the name of his queen, the infanta Maria
Theresa. By this France obtained Lille, Charleroi, Douai, Tournai,
Oudenarde, &c. The _second peace_ of Aix-la-Chapelle, 18th Oct., 1748,
terminated the Austrian war of succession.
AJACCIO ([.a]-y[.a]ch'[=o]), the capital of Corsica, on the south-west
coast of the island, on a tongue of land projecting into the Gulf of
Ajaccio, the birthplace of Napoleon and the seat of a bishop, with coral
and sardine fisheries, and a considerable trade. There are here a
cathedral, a college with library and museum, marble statue of Napoleon,
monument of the Bonaparte family, &c. Ajaccio is connected by railway with
Bastia and other places, and is becoming a winter resort for people with
weak lungs. Pop. 20,946.
AJAN'TA, a village and ravine of India, in the north-west of the Nizam's
dominions, about 50 miles north-north-east of Aurangabad. The ravine, 4
miles N.W. of the village, is celebrated for its cave temples and
monasteries, twenty-nine in number, excavated out of a wall of almost
perpendicular rock about 250 feet high. They are all richly ornamented with
sculpture, and covered with highly-finished paintings, representing
subjects of almost all kinds. The oldest are assigned to about 200 B.C.,
the most modern to about A.D. 600, and they may be said to furnish a
continuous record of Buddhist art during 800 years, the faith at the latter
date being practically expelled from India.
A'JAX (Gr. _Aias_), the name of two Grecian chiefs who fought against Troy,
the one being son of O[)i]leus, King of Locris, surnamed the Little, the
other son of Telamon, the Great or Telamonian Ajax. The latter was from
Salamis, and sailed with twelve ships to Troy, where he is represented by
Homer as the boldest and handsomest of the Greeks, after Achilles. He had
more than one combat with Hector, against whom he was well matched. On the
death of Achilles, when his arms, which Ajax claimed, were awarded to
Ulysses, he became insane and killed himself. This is the subject of
Sophocles' tragedy _Ajax_. The other Ajax was hardly of less importance as
a champion on the Greek side in the Trojan war. At the fall of Troy he
entered the temple of Pallas Athena and seized Cassandra. He lost his life
during his homeward voyage, either by shipwreck or by a flash of lightning
sent by Athena, who was offended at the violation of her temple.
AJMERE, AJMIR, or AJMER, a British commissionership or province in India,
Rajputana, divided into the two districts of Ajmere and Mairwara (or
Merwara); area, 2711 sq. miles. The surface of the province, which is
entirely surrounded by native States, is hilly in the north and west, where
there is a branch of the Aravali range, but level in the south and east.
The soil is partly fertile, but there are large barren sandy plains, and
there are no rivers of any importance. There are a large number of tanks
which collect the water of small streams, and are useful for irrigation.
The province suffered severely from famine in 1899-1900, the population
being reduced by 12 or 13 per cent. Pop. 501,395.--_Ajmere_, the capital,
an ancient city, a favourite residence of the Mogul emperors, is 279 miles
S.W. of Delhi, at the foot of Taragarh Hill (2853 feet), on which is a
fort. It is surrounded by a wall, has well-built streets, and possesses a
Government college, as also Mayo College for Rajput nobles, a Scottish
mission, a mosque that forms one of the finest specimens of early
Mahommedan architecture extant, and an old palace of Akbar, now the
treasury. There is a trade in cotton, sugar, salt, &c., and the town is an
important station on the Rajputana railway. Pop. 86,200.
AJOWAN' (_Ptych[=o]tis Ajowan_), an umbelliferous plant cultivated in
India, Persia, and Egypt, the seeds of which are used in cookery and in
medicine, having carminative properties. The seeds much resemble caraway
seeds, have a strong smell of thyme, and are exported in some quantity to
Europe as a source of _thymol_, now so well known.
AJU'GA, a genus of plants belonging to the labiate family. See _Bugle_.
AJ'UTAGE, a short tube of a tapering shape fitting into the side of a
reservoir or vessel to regulate the discharge of water from it. Also, the
nozzle of a tube for regulating the discharge of water to form a _jet
d'eau_.
AKABAH', Gulf of, an arm of the Red Sea, on the east side of the Peninsula
of Sinai, which separates it from the Gulf of Suez; nearly 100 miles long.
The village of Akabah, at the northern extremity of the gulf, is supposed
to be near the site of the _Ezion-geber_ of the Old Testament; and here
also was Elath, long a place of note. Akabah still carries on a small
trade. It was captured by the Arabs in 1917.
AKAGAMASEKI. Same as _Simonoseki_.
AKAROID RESIN, a resin obtained from some of the grass-trees of Australia,
used in varnishes.
AKASSA, a seaport of Southern Nigeria, on a small island nearly opposite
the chief mouth of the Niger. There are here engineering and other works,
at which ships may be repaired, belonging to the Government.
AK'BAR (that is 'very great'), a Mogul emperor, the greatest Asiatic prince
of modern times. He was born at Amerkote, in Sind, in 1542, succeeded his
father, Humayun, a grandson of Sultan Baber, at the age of thirteen, and
governed first under the guardianship of his minister, Beyram, but took the
chief power into his own hands in 1560. He fought with distinguished valour
against his foreign foes and rebellious subjects, conquering all his
enemies, and extending the limits of the empire farther than they had ever
been before, although on his accession they embraced only a small part of
the former Mogul Empire. Although a Mohammedan by birth, he abandoned Islam
and founded a new religion which he called 'Divine Faith' (_Diu-i-Olahi_).
His contemporaries bestowed upon him the title of 'Guardian of Mankind'. He
was also a generous patron of literature, and commissioned the Jesuit
missionary, Jerome Xavier, to translate the four gospels into Persian. His
government was remarkable for its mildness and tolerance towards all sects;
he was indefatigable in his attention to the internal administration of his
empire, and instituted inquiries into the population, character, and
productions of each province. The result of his statistical labours, as
well as a history of his reign, were collected by his minister, Abul Fazl,
in a work called _Akbar-Nameh_ (Book of Akbar), the third part of which,
entitled _Ayini-Akbari_ (Institutes of Akbar), was published in an English
translation at Calcutta (1783-6, 3 vols.), and reprinted in London. He died
in 1605. His mausoleum at Secundra, near Agra, is a fine example of
Mohammedan architecture. Cf. V. A. Smith, _Akbar, The Great Mogul_.
AKEE' (_Blighia sap[)i]da_), a tree of the nat. ord. Sapindaceae, much
esteemed for its fruit. The leaves are somewhat similar to those of the
ash; the flowers are small and white, and produced in branched spikes. The
fruit is lobed and ribbed, of a dull orange colour, and contains several
large black seeds, embedded in a succulent and slightly bitter arillus of a
pale straw colour, which is eaten when cooked. The akee is a native of
Guinea, from whence it was carried to the West Indies by Captain Bligh in
1793.
A KEMPIS, Thomas. See _Thomas a Kempis_.
AKEN ([:a]'ken), a Prussian town, province of Saxony, on the left bank of
the Elbe, with manufactures of tobacco, cloth, beetroot sugar, leather, &c.
Pop. 7358.
A'KENSIDE, Mark, a poet and physician, born in 1721, at
Newcastle-upon-Tyne, died in London in 1770. He was the son of a butcher,
and was sent to the University of Edinburgh to qualify for the ministry,
but chose the study of medicine instead. After three years' residence at
Edinburgh he went to Leyden, and in 1744 became Doctor of Physic. In the
same year he published the _Pleasures of Imagination_, which he is said to
have written in Edinburgh, and which was translated into French by Baron
d'Holbach (1769). In 1746 he wrote his much-praised _Hymn to the Naiads_.
Having settled in London, he became a fellow of the Royal Society, and was
admitted into the College of Physicians. In 1759 he was appointed first
assistant and afterwards head physician to St. Thomas's Hospital. In his
later days he wrote little poetry, but published several medical essays and
observations. The place of Akenside as a poet is not very high, though Dr.
Johnson praised the blank verse of his poems, and his somewhat cumbrous
_Pleasures of Imagination_ was once considered one of the most pleasing
didactic poems in our language.
AKERMANN', a fortified town and seaport in Bessarabia, near the mouth of
the Dniester, with a good port. The vicinity produces quantities of salt,
and also fine grapes from which excellent wine is made. A treaty was signed
here, 6th Oct., 1826, between Russia and the Porte, by which Moldavia,
Walachia, and Serbia were released from all but nominal dependence on
Turkey. Pop. 40,000.
AKHALZIK, or ACHALZIK ([.a]-_h_[.a]l'tsik), a town of Russia in Asia, in
the Trans-Caucasian government of Tiflis, 97 miles west of Tiflis, with a
citadel. It was taken by the Russians in 1828. Pop. 15,977.
AK-HISSAR ('white castle'), a town in Asia Minor, 46 miles N.E. of Smyrna,
occupying the site of the ancient Thyatira, relics of which city are here
abundant. Here the Emperor Valens defeated the usurper Procopius in 366,
and Murad defeated the Prince of Aidin in 1425. Pop. 20,000.
AKHTYRKA ([.a]_h_-tir'k[.a]), a cathedral town of the Ukraine, government
of Kharkov, with a good trade and some manufactures. Pop. 31,918.
AKJERMANN ([.a]k-yer-m[.a]n'). Same as _Akermann_.
AKKAD, the northern portion of ancient Babylonia occupied by the earliest
Semitic invaders when the southern portion was Sumer (or Sumeria) and
occupied by non-Semites. There was also a city of the same name, the
Biblical Accad (_Gen._ x), which was prominent before 2000 B.C. Its ruins
were unearthed between 1917 and 1919. See _Babylonia_.
AKKAS, a dwarfish race of Central Africa, dwelling in scattered settlements
to the north-west of Lake Albert Nyanza, about lat. 3deg N., lon. 29deg E.
Their height averages about 4-1/2 feet; they are of a brownish or coffee
colour; head large, jaws projecting (or prognathous), ears large, hands
small. They are timid and suspicious, and live almost entirely by the
chase, being exceedingly skilful with the bow and arrow. They were first
seen by the traveller G. A. Schweinfurth in 1870.
AKMOLINSK', a Russian province in Central Asia, largely consisting of
steppes and wastes; the chief rivers are the Ishim and Sari-Su; and it
contains the larger part of Lake Balkash. Capital, Omsk. Area, about
225,070 sq. miles. Pop. 1,523,700.--_Akmolinsk_ is a place of some
importance for its caravan trade. Pop. 11,000.
AKO'LA, a town of India, in Berar, the residence of the commissioner of
Berar, on the River Morna, 150 miles W. by S. of Nagpur; with walls and a
fort, and some trade in cotton. Pop. 29,289.
AK'RON, a town of the United States, in Ohio, 100 miles N.E. of Columbus,
on an elevated site. Being furnished with ample water-power by the Little
Cuyahoga, it possesses large flour-mills, woollen factories, manufactures
of iron goods, &c. In the vicinity extensive beds of mineral paint are
worked. Pop. (1920), 208,435.
AKSU' ('white water'), a town of Eastern or Chinese Turkestan, 300 miles
from Kashgar, in the valley of the Aksu. It is an important centre of trade
between Russia, China, and Tartary, and has manufactures of cotton cloth,
leather, and metal goods. Formerly the residence of the kings of Kashgar
and Yarkand. Pop. 30,000.
AKYAB', a seaport of Lower Burmah, capital of the province of Arracan, at
the mouth of the River Kuladan or Akyab, of recent upgrowth, well built,
possessing a good harbour, and carrying on an important trade, its chief
exports being rice and petroleum. Pop. 35,680.
AL, the article in the Arabic language. It appears in English words derived
from the Arabic, such as Algebra, Alchemy, Alcove.
ALABAMA (al-a-b[.a]'ma), one of the United States, bounded by Tennessee,
Georgia, Florida, the Gulf of Mexico, and Mississippi; area, 51,998 sq.
miles. The southern part, bordering on the Gulf of Mexico and Florida, is
low and level, and wooded largely with pine, hence known as the 'pine-woods
region'; the middle is hilly, with some tracts of level sand or prairies;
the north is broken and mountainous. The State is intersected by the Rivers
Alabama, Tombigbee, Mobile, Coosa, Tallapoosa, Tennessee, &c., some of them
navigable for several hundred miles. The soil is various, being in some
places, particularly in the south, sandy and barren, but in most parts is
fertile, especially in the river valleys and in the centre, where there is
a very fertile tract known as the 'cotton belt'. The climate in general is
warm, and in the lowlying lands skirting the rivers is rather unhealthy. In
the more elevated parts it is healthy and agreeable, the winters being mild
and the summers tempered by breezes from the Gulf of Mexico. The staple
production is cotton, especially in the middle and south, where rice and
sugar are also grown; in the north the cereals (above all maize) are the
principal crops. Alabama possesses extensive beds of iron ore and coal,
with marble, granite, and other minerals; and coal and iron mining, and the
smelting and working of iron, are now important industries. The manufacture
of cotton goods is extensively carried on. The foreign trade is
concentrated in Mobile, whence cotton is the principal export. The State
sends eight representatives to Congress. Its principal towns are
Montgomery, the seat of government, and Mobile, the chief port. There is a
State university at Tuscaloosa, a university connected with the Methodist
Episcopal body, several State normal colleges, besides professional
schools, &c., in the principal towns. Alabama became a State in 1819. It
was one of the slave States. Pop. (1920), 2,348,174.
ALABAMA, a river of the United States, in the State of Alabama, formed by
the junction of the Coosa and the Tallapoosa. After a course of 300 miles
it joins the Tombigbee and assumes the name of the Mobile.
ALABAMA, The, a ship built at Birkenhead to act as a privateer in the
service of the Confederate States of North America during the civil war
begun in 1861. She was a wooden screw steamer with two engines of 350 h.p.
each, 1040 tons burden, and carried eight 32-pounders. Before she was
launched her destination was made known to the British Government, but
owing to some legal formalities the orders given for her detention did not
reach Liverpool till the day after she had left that port (29th July,
1862). She received her armament and stores at the Azores, and entered on
her destructive career, capturing and burning merchant vessels, till she
was sunk in a fight with the Federal war steamer _Kearsarge_, off
Cherbourg, 19th June, 1864. As early as the winter of 1862 the United
States Government declared that they held themselves entitled at a suitable
period to demand full compensation from Britain for the damages inflicted
on American property by the _Alabama_ and several other cruisers that had
been built, supplied, or recruited in British ports or waters. After a long
series of negotiations it was agreed to submit the final settlement of the
question to a court of arbitration, consisting of representatives of
Britain and the United States, and of three other members, appointed by the
King of Italy, the President of Switzerland, and the Emperor of Brazil.
This court met at Geneva, 17th Dec., 1871, and a claim for indirect damages
to American commerce having been abandoned by the United States Government,
the decree was given in Sept., 1872, that Britain was liable to the United
States in damages to the amount of 15,500,000 dollars (about L3,229,200).
After all awards were made to private claimants about 8,000,000 dollars
still remain unclaimed.
ALABANDITE, or MANGANBLENDE, a black submetallic mineral.