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THE ENCYCLOPAEDIA BRITANNICA - ELEVENTH EDITION

FIRST edition, published in three volumes, 1768-1771. SECOND edition, published in ten volumes, 1777-1784. THIRD edition, published in eighteen volumes, 1788-1797. FOURTH edition, published in twenty volumes, 1801-1810. FIFTH edition, published in twenty volumes, 1815-1817. SIXTH edition, published in twenty volumes, 1823-1824. SEVENTH edition, published in twenty-one volumes, 1830-1842. EIGHTH edition, published in twenty-two volumes, 1853-1860. NINTH edition, published in twenty-five volumes, 1875-1889. TENTH edition, ninth edition and eleven supplementary volumes, 1902-1903. ELEVENTH edition, published in twenty-nine volumes, 1910-1911.

THE ENCYCLOPAEDIA BRITANNICA

A DICTIONARY OF ARTS, SCIENCES, LITERATURE AND GENERAL INFORMATION

ELEVENTH EDITION

VOLUME II

ANDROS to AUSTRIA

[E-Text Edition of Volume II - Part 01 of 16 - ANDROS to ANISE]



INITIALS USED IN VOLUME II. TO IDENTIFY INDIVIDUAL CONTRIBUTORS, WITH THE HEADINGS OF THE ARTICLES IN THIS VOLUME SO SIGNED.

[Note: Listing adjusted to E-Text Edition of Volume II, Part 01. The full list of contributors appear in the complete E-text Edition of Volume II. A complete list of all contributors to the encyclopaedia, appears in the final volume.]

A.B.R. - ALFRED BARTON RENDLE, F.R S F.L.S. D.Sc. Keeper of the Department of Botany, British Museum.

- ANGIOSPERMS

C.Pl. - REV. CHARLES PLUMMER, M.A. Fellow of Corpus Christi College, Oxford. Ford's Lecturer, 1901. Author of Life and Times of Alfred the Great; &c.

- ANGLO-SAXON CHRONICLE

E.O. - EDMUND OWEN, M.B., F.R.C.S., LL.D., D.SC. Consulting Surgeon to St Mary's Hospital, London, and to the Children's Hospital, Great Ormond Street. Late Examiner in Surgery at the Universities of Cambridge, Durham and London. Author of A Manual of Anatomy for Senior Students.

- ANEURYSM

H.M.C. - HECTOR MUNRO CHADWICK, M.A. Fellow and Librarian of Clare College, Cambridge. Author of Studies on Anglo-Saxon Institutions.

- ANGLI; ANGLO-SAXONS

H.Sm. - HUGH SHERINGHAM. Angling Editor of The Field (London).

- ANGLING

I.B.B. - ISAAC BAYLEY BALFOUR, F.R.S., M.D. King's Botanist in Scotland. Regius Keeper of Royal Botanic Garden, Edinburgh. Professor of Botany in the University of Edinburgh. Regius Professor of Botany in the University of Glasgow, 1879-1884. Sherardian Professor of Botany in the University of Oxford, 1884-1888.

- ANGIOSPERMS (in part).

J.G.C.A. - JOHN GEORGE CLARK ANDERSON, M.A. Student, Censor and Tutor of Christ Church, Oxford. Craven Fellow, 1896. Formerly Fellow of Lincoln College, Oxford. Joint-author of Studica Pontica.

- ANGORA

L.J.S. - LEONARD JAMES SPENCER, M.A., F.G.S. Department of Mineralogy, British Museum. Formerly Scholar of Sidney Sussex College, Cambridge, and Harkness Scholar. Editor of the Mineralogical Magazine.

- ANHYDRITE

L.M.Br. - LOUIS MAURICE BRANDIN, M.A. Fielden Professor of French and of Romance Philology in the University of London.

- ANGLO-NORMAN LITERATURE

N.W.T. - NORTHCOTE WHITBRIDGE THOMAS, M.A. Government Anthropologist to Southern Nigeria. Corresponding Member of the Societe d'Anthropologie de Paris. Author of Thought Transference; Kinship and Marriage in Australia; &c.

- ANIMAL-WORSHIP, ANIMISM

P.C.M. - PETER CHALMERS MITCHELL, F.R.S., F.Z.S., D.Sc., LL.D. Secretary to the Zoological Society of London from 1903. University Demonstrator in Comparative Anatomy and Assistant to Linacre Professor at Oxford, 1888-1891. Lecturer on Biology at Charing Cross Hospital, 1892-1894; at London Hospital, 1894. Examiner in Biology to the Royal College of Physicians, 1892-1896, 1901-1903. Examiner in Zoology to the University of London, 1903.

- ANIMAL

P.C.Y. - PHILIP CHESNEY YORKE, M.A. Magdalen College, Oxford.

- ANGLESEY, 1st EARL OF

P.Vi. - PAUL VINOGRADOFF, D.C.L. (Oxford), LL.D. (Cambridge and Harvard). Corpus Professor of Jurisprudence in the University of Oxford. Fellow of the British Academy. Honorary Professor of History in the University of Moscow. Author of Villainage in England; English Society in the 11th Century; &c.

- ANGLO-SAXON LAW

T.Ba. - SIR THOMAS BARCLAY, M.P.

Member of the Institute of International Law. Member of the Supreme Council of the Congo Free State. Officer of the Legion of Honour. Author of Problems of International Practice and Diplomacy; &c. M.P. for Blackburn, 1910.

- ANGARY

W.H.Be. - WILLIAM HENRY BENNETT, M.A., D.D., D.LITT. (Cantab.). Professor of Old Testament Exegesis in New and Hackney Colleges, London. Formerly Fellow of St John's College, Cambridge. Lecturer in Hebrew at Firth College, Sheffield. Author of Religion of the Post-Exilic Prophets; &c.

- ANGEL

W.H.Di. - WILLIAM HENRY DINES, F.R.S.

- ANEMOMETER

W.M.R. - WILLIAM MICHAEL ROSSETTI. See the biographical article: ROSSETTI, DANTE GABRIEL.

- ANGELICO, FRA

PRINCIPAL UNSIGNED ARTICLES

Anglican Communion. Angola.

[Note regarding E-text edition: Volume and page numbers have been incorporated into the text at the first paragraph break of each page as: v.02 p.0001 ]



THE ENCYCLOPAEDIA BRITANNICA

ELEVENTH EDITION

VOLUME II, PART I

[v.02 p.0001]

ANDROS, SIR EDMUND (1637-1714), English colonial governor in America, was born in London on the 6th of December 1637, son of Amice Andros, an adherent of Charles I., and the royal bailiff of the island of Guernsey. He served for a short time in the army of Prince Henry of Nassau, and in 1660-1662 was gentleman in ordinary to the queen of Bohemia (Elizabeth Stuart, daughter of James I. of England). He then served against the Dutch, and in 1672 was commissioned major in what is said to have been the first English regiment armed with the bayonet. In 1674 he became, by the appointment of the duke of York (later James II.), governor of New York and the Jerseys, though his jurisdiction over the Jerseys was disputed, and until his recall in 1681 to meet an unfounded charge of dishonesty and favouritism in the collection of the revenues, he proved himself to be a capable administrator, whose imperious disposition, however, rendered him somewhat unpopular among the colonists. During a visit to England in 1678 he was knighted. In 1686 he became governor, with Boston as his capital, of the "Dominion of New England," into which Massachusetts (including Maine), Plymouth, Rhode Island, Connecticut and New Hampshire were consolidated, and in 1688 his jurisdiction was extended over New York and the Jerseys. But his vexatious interference with colonial rights and customs aroused the keenest resentment, and on the 18th of April 1689, soon after news of the arrival of William, prince of Orange, in England reached Boston, the colonists deposed and arrested him. In New York his deputy, Francis Nicholson, was soon afterwards deposed by Jacob Leisler (q.v.); and the inter-colonial union was dissolved. Andros was sent to England for trial in 1690, but was immediately released without trial, and from 1692 until 1698 he was governor of Virginia, but was recalled through the agency of Commissary James Blair (q.v.), with whom he quarrelled. In 1693-1694 he was also governor of Maryland. From 1704 to 1706 he was governor of Guernsey. He died in London in February 1714 and was buried at St. Anne's, Soho.

See The Andros Tracts (3 vols., Boston, 1869-1872).



ANDROS, or ANDRO, an island of the Greek archipelago, the most northerly of the Cyclades, 6 m. S.E. of Euboea, and about 2 m. N. of Tenos; it forms an eparchy in the modern kingdom of Greece. It is nearly 25 m. long, and its greatest breadth is 10 m. Its surface is for the most part mountainous, with many fruitful and well-watered valleys. Andros, the capital, on the east coast, contains about 2000 inhabitants. The ruins of Palaeopolis, the ancient capital, are on the west coast; the town possessed a famous temple, dedicated to Bacchus. The island has about 18,000 inhabitants.

The island in ancient times contained an Ionian population, perhaps with an admixture of Thracian blood. Though originally dependent on Eretria, by the 7th century B.C. it had become sufficiently prosperous to send out several colonies to Chalcidice (Acanthus, Stageirus, Argilus, Sane). In 480 it supplied ships to Xerxes and was subsequently harried by the Greek fleet. Though enrolled in the Delian League it remained disaffected towards Athens, and in 447 had to be coerced by the settlement of a cleruchy. In 411 Andros proclaimed its freedom and in 408 withstood an Athenian attack. As a member of the second Delian League it was again controlled by a garrison and an archon. In the Hellenistic period Andros was contended for as a frontier-post by the two naval powers of the Aegean Sea, Macedonia and Egypt. In 333 it received a Macedonian garrison from Antipater; in 308 it was freed by Ptolemy I. In the Chremonidean War (266-263) it passed again to Macedonia after a battle fought off its shores. In 200 it was captured by a combined Roman, Pergamene and Rhodian fleet, and remained a possession of Pergamum until the dissolution of that kingdom in 133 B.C. Before falling under Turkish rule, Andros was from A.D. 1207 till 1566 governed by the families Zeno and Sommariva under Venetian protection.



ANDROTION (c. 350 B.C.), Greek orator, and one of the leading politicians of his time, was a pupil of Isocrates and a contemporary of Demosthenes. He is known to us chiefly from the speech of Demosthenes, in which he was accused of illegality in proposing the usual honour of a crown to the Council of Five Hundred at the expiration of its term of office. Androtion filled several important posts, and during the Social War was appointed extraordinary commissioner to recover certain arrears of taxes. Both Demosthenes and Aristotle (Rhet. iii. 4) speak favourably of his powers as an orator. He is said to have gone into exile at Megara, and to have composed an Atthis, or annalistic account of Attica from the earliest times to his own days (Pausanias vi. 7; x. 8). It is disputed whether the annalist and orator are identical, but an Androtion who wrote on agriculture is certainly a different person. Professor Gaetano de Sanctis (in L'Attide di Androzione e un papiro di Oxyrhynchos, Turin, 1908) attributes to Androtion, the atthidographer, a 4th-century historical fragment, discovered by B.P. Grenfell and A.S. Hunt (Oxyrhynchus Papyri, vol. v.). Strong arguments against this view are set forth by E.M. Walker in the Classical Review, May 1908.

[v.02 p.0002]



ANDUJAR (the anc. Slilurgi), a town of southern Spain, in the province of Jaen; on the right bank of the river Guadalquivir and the Madrid-Cordova railway. Pop. (1900) 16,302. Andujar is widely known for its porous earthenware jars, called alcarrazas, which keep water cool in the hottest weather, and are manufactured from a whitish clay found in the neighbourhood.



ANECDOTE (from [Greek: an]-, privative, and [Greek: ekdidomi], to give out or publish), a word originally meaning something not published. It has now two distinct significations. The primary one is something not published, in which sense it has been used to denote either secret histories—Procopius, e.g., gives this as one of the titles of his secret history of Justinian's court—or portions of ancient writers which have remained long in manuscript and are edited for the first time. Of such anecdota there are many collections; the earliest was probably L.A. Muratori's, in 1709. In the more general and popular acceptation of the word, however, anecdotes are short accounts of detached interesting particulars. Of such anecdotes the collections are almost infinite; the best in many respects is that compiled by T. Byerley (d. 1826) and J. Clinton Robertson (d. 1852), known as the Percy Anecdotes (1820-1823).



ANEL, DOMINIQUE (1679-1730), French surgeon, was born at Toulouse about 1679. After studying at Montpellier and Paris, he served as surgeon-major in the French army in Alsace; then after two years at Vienna he went to Italy and served in the Austrian army. In 1710 he was teaching surgery in Rouen, whence he went to Genoa, and in 1716 he was practising in Paris. He died about 1730. He was celebrated for his successful surgical treatment of fistula lacrymalis, and while at Genoa invented for use in connexion with the operation the fine-pointed syringe still known by his name.



ANEMOMETER (from Gr. [Greek: anemos], wind, and [Greek: metron], a measure), an instrument for measuring either the velocity or the pressure of the wind. Anemometers may be divided into two classes, (1) those that measure the velocity, (2) those that measure the pressure of the wind, but inasmuch as there is a close connexion between the pressure and the velocity, a suitable anemometer of either class will give information about both these quantities.

Velocity anemometers may again be subdivided into two classes, (1) those which do not require a wind vane or weathercock, (2) those which do. The Robinson anemometer, invented (1846) by Dr. Thomas Romney Robinson, of Armagh Observatory, is the best-known and most generally used instrument, and belongs to the first of these. It consists of four hemispherical cups, mounted one on each end of a pair of horizontal arms, which lie at right angles to each other and form a cross. A vertical axis round which the cups turn passes through the centre of the cross; a train of wheel-work counts up the number of turns which this axis makes, and from the number of turns made in any given time the velocity of the wind during that time is calculated. The cups are placed symmetrically on the end of the arms, and it is easy to see that the wind always has the hollow of one cup presented to it; the back of the cup on the opposite end of the cross also faces the wind, but the pressure on it is naturally less, and hence a continual rotation is produced; each cup in turn as it comes round providing the necessary force. The two great merits of this anemometer are its simplicity and the absence of a wind vane; on the other hand it is not well adapted to leaving a record on paper of the actual velocity at any definite instant, and hence it leaves a short but violent gust unrecorded. Unfortunately, when Dr. Robinson first designed his anemometer, he stated that no matter what the size of the cups or the length of the arms, the cups always moved with one-third of the velocity of the wind. This result was apparently confirmed by some independent experiments, but it is very far from the truth, for it is now known that the actual ratio, or factor as it is commonly called, of the velocity of the wind to that of the cups depends very largely on the dimensions of the cups and arms, and may have almost any value between two and a little over three. The result has been that wind velocities published in many official publications have often been in error by nearly 50%.

The other forms of velocity anemometer may be described as belonging to the windmill type. In the Robinson anemometer the axis of rotation is vertical, but with this subdivision the axis of rotation must be parallel to the direction of the wind and therefore horizontal. Furthermore, since the wind varies in direction and the axis has to follow its changes, a wind vane or some other contrivance to fulfil the same purpose must be employed. This type of instrument is very little used in England, but seems to be more in favour in France. In cases where the direction of the air motion is always the same, as in the ventilating shafts of mines and buildings for instance, these anemometers, known, however, as air meters, are employed, and give most satisfactory results.

Anemometers which measure the pressure may be divided into the plate and tube classes, but the former term must be taken as including a good many miscellaneous forms. The simplest type of this form consists of a flat plate, which is usually square or circular, while a wind vane keeps this exposed normally to the wind, and the pressure of the wind on its face is balanced by a spring. The distortion of the spring determines the actual force which the wind is exerting on the plate, and this is either read off on a suitable gauge, or leaves a record in the ordinary way by means of a pen writing on a sheet of paper moved by clockwork. Instruments of this kind have been in use for a long series of years, and have recorded pressures up to and even exceeding 60 lb per sq. ft., but it is now fairly certain that these high values are erroneous, and due, not to the wind, but to faulty design of the anemometer.

The fact is that the wind is continually varying in force, and while the ordinary pressure plate is admirably adapted for measuring the force of a steady and uniform wind, it is entirely unsuitable for following the rapid fluctuations of the natural wind. To make matters worse, the pen which records the motion of the plate is often connected with it by an extensive system of chains and levers. A violent gust strikes the plate, which is driven back and carried by its own momentum far past the position in which a steady wind of the same force would place it; by the time the motion has reached the pen it has been greatly exaggerated by the springiness of the connexion, and not only is the plate itself driven too far back, but also its position is wrongly recorded by the pen; the combined errors act the same way, and more than double the real maximum pressure may be indicated on the chart.

A modification of the ordinary pressure-plate has recently been designed. In this arrangement a catch is provided so that the plate being once driven back by the wind cannot return until released by hand; but the catch does not prevent the plate being driven back farther by a gust stronger than the last one that moved it. Examples of these plates are erected on the west coast of England, where in the winter fierce gales often occur; a pressure of 30 lb per sq. ft. has not been shown by them, and instances exceeding 20 lb are extremely rare.

Many other modifications have been used and suggested. Probably a sphere would prove most useful for a pressure anemometer, since owing to its symmetrical shape it would not require a weathercock. A small light sphere hanging from the end of 30 or 40 ft. of fine sewing cotton has been employed to measure the wind velocity passing over a kite, the tension of the cotton being recorded, and this plan has given satisfactory results.

Lind's anemometer, which consists simply of a U tube containing liquid with one end bent into a horizontal direction to face the wind, is perhaps the original form from which the tube class of instrument has sprung. If the wind blows into the mouth of a tube it causes an increase of pressure inside and also of course an equal increase in all closed vessels with which the mouth is in airtight communication. If it blows horizontally over the open end of a vertical tube it causes a decrease of pressure, but this fact is not of any practical use in anemometry, because the magnitude of the decrease depends on the wind striking the tube exactly at right angles to its axis, the most trifling departure from the true direction causing great variations in the magnitude. The pressure tube anemometer (fig. 1) utilizes the increased pressure in the open mouth of a straight tube facing the wind, and the decrease of pressure caused inside when the wind blows over a ring of small holes drilled through the metal of a vertical tube which is closed at the upper end. The pressure differences on which the action depends are very small, and special means are required to register them, but in the ordinary form of recording anemometer (fig. 2), any wind capable of turning the vane which keeps the mouth of the tube facing the wind is capable of registration.

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The great advantage of the tube anemometer lies in the fact that the exposed part can be mounted on a high pole, and requires no oiling or attention for years; and the registering part can be placed in any convenient position, no matter how far from the external part. Two connecting tubes are required. It might appear at first sight as though one connexion would serve, but the differences in pressure on which these instruments depend are so minute, that the pressure of the air in the room where the recording part is placed has to be considered. Thus if the instrument depends on the pressure or suction effect alone, and this pressure or suction is measured against the air pressure in an ordinary room, in which the doors and windows are carefully closed and a newspaper is then burnt up the chimney, an effect may be produced equal to a wind of 10 m. an hour; and the opening of a window in rough weather, or the opening of a door, may entirely alter the registration.



The connexion between the velocity and the pressure of the wind is one that is not yet known with absolute certainty. Many text-books on engineering give the relation P.005 v^2 when P is the pressure in lb per sq. ft. and v the velocity in miles per hour. The history of this untrue relation is curious. It was given about the end of the 18th century as based on some experiments, but with a footnote stating that little reliance could be placed on it. The statement without the qualifying note was copied from book to book, and at last received general acceptance. There is no doubt that under average conditions of atmospheric density, the .005 should be replaced by .003, for many independent authorities using different methods have found values very close to this last figure. It is probable that the wind pressure is not strictly proportional to the extent of the surface exposed. Pressure plates are generally of moderate size, from a half or quarter of a sq. ft. up to two or three sq. ft., are round or square, and for these sizes, and shapes, and of course for a flat surface, the relation P.003 v^2 is fairly correct.

In the tube anemometer also it is really the pressure that is measured, although the scale is usually graduated as a velocity scale. In cases where the density of the air is not of average value, as on a high mountain, or with an exceptionally low barometer for example, an allowance must be made. Approximately 1-1/2% should be added to the velocity recorded by a tube anemometer for each 1000 ft. that it stands above sea-level.

(W.H. Di.)



ANEMONE, or WIND-FLOWER (from the Gr. [Greek: anemos], wind), a genus of the buttercup order (Ranunculaceae), containing about ninety species in the north and south temperate zones. Anemone nemorosa, wood anemone, and A. Pulsatilla, Pasque-flower, occur in Britain; the latter is found on chalk downs and limestone pastures in some of the more southern and eastern counties. The plants are perennial herbs with an underground rootstock, and radical, more or less deeply cut, leaves. The elongated flower stem bears one or several, white, red, blue or rarely yellow, flowers; there is an involucre of three leaflets below each flower. The fruits often bear long hairy styles which aid their distribution by the wind. Many of the species are favourite garden plants; among the best known is Anemone coronaria, often called the poppy anemone, a tuberous-rooted plant, with parsley-like divided leaves, and large showy poppy-like blossoms on stalks of from 6 to 9-in. high; the flowers are of various colours, but the principal are scarlet, crimson, blue, purple and white. There are also double-flowered varieties, in which the stamens in the centre are replaced by a tuft of narrow petals. It is an old garden favourite, and of the double forms there are named varieties. They grow best in a loamy soil, enriched with well-rotted manure, which should be dug in below the tubers. These may be planted in October, and for succession in January, the autumn-planted ones being protected by a covering of leaves or short stable litter. They will flower in May and June, and when the leaves have ripened should be taken up into a dry room till planting time. They are easily raised from the seed, and a bed of the single varieties is a valuable addition to a flower-garden, as it affords, in a warm situation, an abundance of handsome and often brilliant spring flowers, almost as early as the snowdrop or crocus. The genus contains many other lively spring-blooming plants, of which A. hortensis and A. fulgens have less divided leaves and splendid rosy-purple or scarlet flowers; they require similar treatment. Another set is represented by A. Pulsatilla, the Pasque-flower, whose violet blossoms have the outer surface hairy; these prefer a calcareous soil. The splendid A. japonica, and its white variety called Honorine Joubert, the latter especially, are amongst the finest of autumn-blooming hardy perennials; they grow well in light soil, and reach 2-1/2 to 3 ft. in height, blooming continually for several weeks. A group of dwarf species, represented by the native British A. nemorosa and A. apennina, are amongst the most beautiful of spring flowers for planting in woods and shady places.

The genus Hepatica is now generally included in anemone as a subgenus. The plants are known in gardens as hepaticas, and are varieties of the common South European A. Hepatica; they are charming spring-flowering plants with usually blue flowers.



ANENCLETUS, or ANACLETUS, second bishop of Rome. About the 4th century he is treated in the catalogues as two persons—Anacletus and Cletus. According to the catalogues he occupied the papal chair for twelve years (c. 77-88).



ANERIO, the name of two brothers, musical composers, very great Roman masters of 16th-century polyphony. Felice, the elder, was born about 1560, studied under G.M. Nanino and succeeded Palestrina in 1594 as composer to the papal chapel. Several masses and motets of his are printed in Proske's Musica Divina and other modern anthologies, and it is hardly too much to say that they are for the most part worthy of Palestrina himself. The date of his death is conjecturally given as 1630. His brother, Giovanni Francesco, was born about 1567, and seems to have died about 1620. The occasional attribution of some of his numerous compositions to his elder brother is a pardonable mistake, if we may judge by the works that have been reprinted. But the statement, which continues to be repeated in standard works of reference, that "he was one of the first of Italians to use the quaver and its subdivisions" is incomprehensible. Quavers were common property in all musical countries quite early in the 16th century, and semiquavers appear in a madrigal of Palestrina published in 1574. The two brothers are probably the latest composers who handled 16th-century music as their mother-language; suffering neither from the temptation to indulge even in such mild neologisms as they might have learnt from the elder brother's master, Nanino, nor from the necessity of preserving their purity of style by a mortified negative asceticism. They wrote pure polyphony because they understood it and loved it, and hence their work lives, as neither the progressive work of their own day nor the reactionary work of their imitators could live. The 12-part Stabat Mater in the seventh volume of Palestrina's complete works has been by some authorities ascribed to Felice Anerio.

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ANET, a town of northern France, in the department of Eure-et-Loir, situated between the rivers Eure and Vegre, 10 m. N.E. of Dreux by rail. Pop. (1906) 1324. It possesses the remains of a magnificent castle, built in the middle of the 16th century by Henry II. for Diana of Poitiers. Near it is the plain of Ivry, where Henry IV. defeated the armies of the League in 1590.



ANEURIN, or ANEIRIN, the name of an early 7th-century British (Welsh) bard, who has been taken by Thomas Stephens (1821-1875), the editor and translator of Aneurin's principal epic poem Gododin, for a son of Gildas, the historian. Gododin is an account of the British defeat (603) by the Saxons at Cattraeth (identified by Stephens with Dawstane in Liddesdale), where Aneurin is said to have been taken prisoner; but the poem is very obscure and is differently interpreted. It was translated and edited by W.F. Skene in his Four Ancient Books of Wales (1866), and Stephens' version was published by the Cymmrodorion Society in 1888. See CELT: Literature (Welsh).



ANEURYSM, or ANEURISM (from Gr. [Greek: aneurisma], a dilatation), a cavity or sac which communicates with the interior of an artery and contains blood. The walls of the cavity are formed either of the dilated artery or of the tissues around that vessel. The dilatation of the artery is due to a local weakness, the result of disease or injury. The commonest cause is chronic inflammation of the inner coats of the artery. The breaking of a bottle or glass in the hand is apt to cut through the outermost coat of the artery at the wrist (radial) and thus to cause a local weakening of the tube which is gradually followed by dilatation. Also when an artery is wounded and the wound in the skin and superficial structures heals, the blood may escape in to the tissues, displacing them, and by its pressure causing them to condense and form the sac-wall. The coats of an artery, when diseased, may be torn by a severe strain, the blood escaping into the condensed tissues which thus form the aneurysmal sac.

The division, of aneurysms into two classes, true and false, is unsatisfactory. On the face of it, an aneurysm which is false is not an aneurysm, any more than a false bank-note is legal tender. A better classification is into spontaneous and traumatic. The man who has chronic inflammation of a large artery, the result, for instance, of gout, arduous, straining work, or kidney-disease, and whose artery yields under cardiac pressure, has a spontaneous aneurysm; the barman or window-cleaner who has cut his radial artery, the soldier whose brachial or femoral artery has been bruised by a rifle bullet or grazed by a bayonet, and the boy whose naked foot is pierced by a sharp nail, are apt to be the subjects of traumatic aneurysm. In those aneurysms which are a saccular bulging on one side of the artery the blood may be induced to coagulate, or may of itself deposit layer upon layer of pale clot, until the sac is obliterated. This laminar coagulation by constant additions gradually fills the aneurysmal cavity and the pulsation in the sac then ceases; contraction of the sac and its contents gradually takes place and the aneurysm is cured. But in those aneurysms which are fusiform dilatations of the vessel there is but slight chance of such cure, for the blood sweeps evenly through it without staying to deposit clot or laminated fibrine.

In the treatment of aneurysm the aim is generally to lower the blood pressure by absolute rest and moderated diet, but a cure is rarely effected except by operation, which, fortunately, is now resorted to more promptly and securely than was previously the case. Without trying the speculative and dangerous method of treatment by compression, or the application of an india rubber bandage, the surgeon now without loss of time cuts down upon the artery, and applies an aseptic ligature close above the dilatation. Experience has shown that this method possesses great advantages, and that it has none of the disadvantages which were formerly supposed to attend it. Saccular dilatations of arteries which are the result of cuts or other injuries are treated by tying the vessel above and below, and by dissecting out the aneurysm. Popliteal, carotid and other aneurysms, which are not of traumatic origin, are sometimes dealt with on this plan, which is the old "Method of Antyllus" with modern aseptic conditions. Speaking generally, if an aneurysm can be dealt with surgically the sooner that the artery is tied the better. Less heroic measures are too apt to prove painful, dangerous, ineffectual and disappointing. For anturysm in the chest or abdomen (which cannot be dealt with by operation) the treatment may be tried of injecting a pure solution of gelatine into the loose tissues of the armpit, so that the gelatine may find its way into the blood stream and increase the chance of curative coagulation in the distant aneurysmal sac.

(E.O.)



ANFRACTUOSITY (from Lat. anfractuosus, winding), twisting and turning, circuitousness; a word usually employed in the plural to denote winding channels such as occur in the depths of the sea, mountains, or the fissures (sulci) separating the convolutions of the brain, or, by analogy, in the mind.



ANGARIA (from [Greek: aggaros], the Greek form of a Babylonian word adopted in Persian for "mounted courier"), a sort of postal system adopted by the Roman imperial government from the ancient Persians, among whom, according to Xenophon (Cyrop. viii. 6; cf. Herodotus viii. 98) it was established by Cyrus the Great. Couriers on horseback were posted at certain stages along the chief roads of the empire, for the transmission of royal despatches by night and day in all weathers. In the Roman system the supply of horses and their maintenance was a compulsory duty from which the emperor alone could grant exemption. The word, which in the 4th century was used for the heavy transport vehicles of the cursus publicus, and also for the animals by which they were drawn, came to mean generally "compulsory service." So angaria, angariare, in medieval Latin, and the rare English derivatives "angariate," "angariation," came to mean any service which was forcibly or unjustly demanded, and oppression in general.



ANGARY (Lat. jus angariae; Fr. droit d'angarie; Ger. Angarie; from the Gr. [Greek: aggareia], the office of an [Greek: aggaros], courier or messenger), the name given to the right of a belligerent to seize and apply for the purposes of war (or to prevent the enemy from doing so) any kind of property on, belligerent territory, including that which may belong to subjects or citizens of a neutral state. Art. 53 of the Regulations respecting the Laws and Customs of War on Land, annexed to the Hague Convention of 1899 on the same subject, provides that railway plant, land telegraphs, telephones, steamers and other ships (other than such as are governed by maritime law), though belonging to companies or private persons, may be used for military operations, but "must be restored at the conclusion of peace and indemnities paid for them." And Art. 54 adds that "the plant of railways coming from neutral states, whether the property of those states or of companies or private persons, shall be sent back to them as soon as possible." These articles seem to sanction the right of angary against neutral property, while limiting it as against both belligerent and neutral property. It may be considered, however, that the right to use implies as wide a range of contingencies as the "necessity of war" can be made to cover.

(T. BA.)



ANGEL, a general term denoting a subordinate superhuman being in monotheistic religions, e.g.. Islam, Judaism, Christianity, and in allied religions, such as Zoroastrianism. In polytheism the grades of superhuman beings are continuous; but in monotheism there is a sharp distinction of kind, as well as degree, between God on the one hand, and all other superhuman beings on the other; the latter are the "angels."

"Angel" is a transcription of the Gr. [Greek: angelos], messenger. [Greek: angelos] in the New Testament, and the corresponding mal'akh in the Old Testament, sometimes mean "messenger," and sometimes "angel," and this double sense is duly represented in the English Versions. "Angel" is also used in the English Version for [Hebrew:] 'Abbir, Ps. lxxviii. 25. (lit. "mighty"), for [Hebrew:] 'Elohim, Ps. viii. 5, and for the obscure [Hebrew:] shin'an, in Ps. lxviii. 17.

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In the later development of the religion of Israel, 'Elohim is almost entirely reserved for the one true God; but in earlier times 'Elohim (gods), bnē 'Elohim, bnē Elim (sons of gods, i.e. members of the class of divine beings) were general terms for superhuman beings. Hence they came to be used collectively of superhuman beings, distinct from Yahweh, and therefore inferior, and ultimately subordinate.[1] So, too, the angels are styled "holy ones,"[2] and "watchers,"[3] and are spoken of as the "host of heaven"[4] or of "Yahweh."[5] The "hosts," [Hebrew:] Sebaoth in the title Yahweh Sebaoth, Lord of Hosts, were probably at one time identified with the angels.[6] The New Testament often speaks of "spirits," [Greek: pneumata].[7] In the earlier periods of the religion of Israel, the doctrine of monotheism had not been formally stated, so that the idea of "angel" in the modern sense does not occur, but we find the Mal'akh Yahweh, Angel of the Lord, or Mal'akh Elohim, Angel of God. The Mal'akh Yahweh is an appearance or manifestation of Yahweh in the form of a man, and the term Mal'akh Yahweh is used interchangeably with Yahweh (cf. Exod. iii. 2, with iii. 4; xiii. 21 with xiv. 19). Those who see the Mal'akh Yahweh say they have seen God.[8] The Mal'akh Yahweh (or Elohim) appears to Abraham, Hagar, Moses, Gideon, &c., and leads the Israelites in the Pillar of Cloud.[9] The phrase Mal'akh Yahweh may have been originally a courtly circumlocution for the Divine King; but it readily became a means of avoiding crude anthropomorphism, and later on, when the angels were classified, the Mal'akh Yahweh came to mean an angel of distinguished rank.[10] The identification of the Mal'akh Yahweh with the Logos, or Second Person of the Trinity, is not indicated by the references in the Old Testament; but the idea of a Being partly identified with God, and yet in some sense distinct from Him, illustrates the tendency of religious thought to distinguish persons within the unity of the Godhead, and foreshadows the doctrine of the Trinity, at any rate in some slight degree.

In the earlier literature the Mal'akh Yahweh or Elohim is almost the only mal'akh ("angel") mentioned. There are, however, a few passages which speak of subordinate superhuman beings other than the Mal'akh Yahweh or Elohim. There are the cherubim who guard Eden. In Gen. xviii., xix. (J) the appearance of Yahweh to Abraham and Lot is connected with three, afterwards two, men or messengers; but possibly in the original form of the story Yahweh appeared alone.[11] At Bethel, Jacob sees the angels of God on the ladder,[12] and later on they appear to him at Mahanaim.[13] In all these cases the angels, like the Mal'akh Yahweh, are connected with or represent a theophany. Similarly the "man" who wrestles with Jacob at Peniel is identified with God.[14] In Isaiah vi. the seraphim, superhuman beings with six wings, appear as the attendants of Yahweh. Thus the pre-exilic literature, as we now have it, has little to say about angels or about superhuman beings other than Yahweh and manifestations of Yahweh; the pre-exilic prophets hardly mention angels.[15] Nevertheless we may well suppose that the popular religion of ancient Israel had much to say of superhuman beings other than Yahweh, but that the inspired writers have mostly suppressed references to them as unedifying. Moreover such beings were not strictly angels.

The doctrine of monotheism was formally expressed in the period immediately before and during the Exile, in Deuteronomy[16] and Isaiah;[17] and at the same time we find angels prominent in Ezekiel who, as a prophet of the Exile, may have been influenced by the hierarchy of supernatural beings in the Babylonian religion, and perhaps even by the angelology of Zoroastrianism.[18] Ezekiel gives elaborate descriptions of cherubim;[19] and in one of his visions he sees seven angels execute the judgment of God upon Jerusalem.[20] As in Genesis they are styled "men," mal'akh for "angel" does not occur in Ezekiel. Somewhat later, in the visions of Zechariah, angels play a great part; they are sometimes spoken of as "men," sometimes as mal'akh, and the Mal'akh Yahweh seems to hold a certain primacy among them.[21] Satan also appears to prosecute (so to speak) the High Priest before the divine tribunal.[22] Similarly in Job the bne Elohim, sons of God, appear as attendants of God, and amongst them Satan, still in his role of public prosecutor, the defendant being Job.[23] Occasional references to "angels" occur in the Psalter;[24] they appear as ministers of God.

In Ps. lxxviii. 49 the "evil angels" of A.V. conveys a false impression; it should be "angels of evil," as R.V., i.e. angels who inflict chastisement as ministers of God.

The seven angels of Ezekiel may be compared with the seven eyes of Yahweh in Zech. iii. 9, iv. 10. The latter have been connected by Ewald and others with the later doctrine of seven chief angels,[25] parallel to and influenced by the Ameshaspentas (Amesha Spenta), or seven great spirits of the Persian mythology, but the connexion is doubtful.

In the Priestly Code, c. 400 B.C., there is no reference to angels apart from the possible suggestion in the ambiguous plural in Genesis i. 26.

During the Persian and Greek periods the doctrine of angels underwent a great development, partly, at any rate, under foreign influences. In Daniel, c. 160 B.C., angels, usually spoken of as "men" or "princes," appear as guardians or champions of the nations; grades are implied, there are "princes" and "chief" or "great princes"; and the names of some angels are known, Gabriel, Michael; the latter is pre-eminent,[26] he is the guardian of Judah. Again in Tobit a leading part is played by Raphael, "one of the seven holy angels."[27]

In Tobit, too, we find the idea of the demon or evil angel. In the canonical Old Testament angels may inflict suffering as ministers of God, and Satan may act as accuser or tempter; but they appear as subordinate to God, fulfilling His will; and not as morally evil. The statement[28] that God "charged His angels with folly" applies to all angels. In Daniel the princes or guardian angels of the heathen nations oppose Michael the guardian angel of Judah. But in Tobit we find Asmodaeus the evil demon, [Greek: to poneros daimonion], who strangles Sarah's husbands, and also a general reference to "a devil or evil spirit," [Greek: pneuma].[29] The Fall of the Angels is not properly a scriptural doctrine, though it is based on Gen. vi. 2, as interpreted by the Book of Enoch. It is true that the bnē Elohim of that chapter are subordinate superhuman beings (cf. above), but they belong to a different order of thought from the angels of Judaism and of Christian doctrine; and the passage in no way suggests that the bne Elohim suffered any loss of status through their act.

The guardian angels of the nations in Daniel probably represent the gods of the heathen, and we have there the first step of the process by which these gods became evil angels, an idea expanded by Milton in Paradise Lost. The development of the doctrine of an organized hierarchy of angels belongs to the Jewish literature of the period 200 B.C. to A.D. 100. In Jewish apocalypses especially, the imagination ran riot on the rank, classes and names of angels; and such works as the various books of Enoch and the Ascension of Isaiah supply much information on this subject.

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In the New Testament angels appear frequently as the ministers of God and the agents of revelation;[30] and Our Lord speaks of angels as fulfilling such functions,[31] implying in one saying that they neither marry nor are given in marriage.[32] Naturally angels are most prominent in the Apocalypse. The New Testament takes little interest in the idea of the angelic hierarchy, but there are traces of the doctrine. The distinction of good and bad angels is recognized; we have names, Gabriel,[33] and the evil angels Abaddon or Apollyon,[34] Beelzebub.[35] and Satan;[36] ranks are implied, archangels,[37] principalities and powers,[38] thrones and dominions.[39] Angels occur in groups of four or seven.[40] In Rev. i.-iii. we meet with the "Angels" of the Seven Churches of Asia Minor. These are probably guardian angels, standing to the churches in the same relation that the "princes" in Daniel stand to the nations; practically the "angels" are personifications of the churches. A less likely view is that the "angels" are the human representatives of the churches, the bishops or chief presbyters. There seems, however, no parallel to such a use of "angel," and it is doubtful whether the monarchical government of churches was fully developed when the Apocalypse was written.

Later Jewish and Christian speculation followed on the lines of the angelology of the earlier apocalypses; and angels play an important part in Gnostic systems and in the Jewish Midrashim and the Kabbala. Religious thought about the angels during the middle ages was much influenced by the theory of the angelic hierarchy set forth in the De Hierarchia Celesti, written in the 5th century in the name of Dionysius the Areopagite and passing for his. The creeds and confessions do not formulate any authoritative doctrine of angels; and modern rationalism has tended to deny the existence of such beings, or to regard the subject as one on which we can have no certain knowledge. The principle of continuity, however, seems to require the existence of beings intermediate between man and God.

The Old Testament says nothing about the origin of angels; but the Book of Jubilees and the Slavonic Enoch describe their creation; and, according to Col. i. 16, the angels were created in, unto and through Christ.

Nor does the Bible give any formal account of the nature of angels. It is doubtful how far Ezekiel's account of the cherubim and Isaiah's account of the seraphim are to be taken as descriptions of actual beings; they are probably figurative, or else subjective visions. Angels are constantly spoken of as "men," and, including even the Angel of Yahweh, are spoken of as discharging the various functions of human life; they eat and drink,[41] walk[42] and speak.[43] Putting aside the cherubim and seraphim, they are not spoken of as having wings. On the other hand they appear and vanish,[44] exercise miraculous powers,[45] and fly.[46] Seeing that the anthropomorphic language used of the angels is similar to that used of God, the Scriptures would hardly seem to require a literal interpretation in either case. A special association is found, both in the Bible and elsewhere, between the angels and the heavenly bodies,[47] and the elements or elemental forces, fire, water, &c.[48] The angels are infinitely numerous.[49]

The function of the angels is that of the supernatural servants of God. His agents and representatives; the Angel of Yahweh, as we have seen, is a manifestation of God. In old times, the bne Elohim and the seraphim are His court, and the angels are alike the court and the army of God; the cherubim are his throne-bearers. In his dealings with men, the angels, as their name implies, are specially His messengers, declaring His will and executing His commissions. Through them he controls nature and man. They are the guardian angels of the nations; and we also find the idea that individuals have guardian angels.[50]. Later Jewish tradition held that the Law was given by angels.[51] According to the Gnostic Basilides, the world was created by angels. Mahommedanism has taken over and further elaborated the Jewish and Christian ideas as to angels.

While the scriptural statements imply a belief in the existence of spiritual beings intermediate between God and men, it is probable that many of the details may be regarded merely as symbolic imagery. In Scripture the function of the angel overshadows his personality; the stress is on their ministry; they appear in order to perform specific acts.

[Footnote 1: E.g. Gen. vi. 2; Job i. 6; Ps. viii. 5, xxix. I.]

[Footnote 2: Zech. xiv. 5.]

[Footnote 3: Dan. iv. 13.]

[Footnote 4: Deut. xvii. 3 (?).]

[Footnote 5: Josh. v. 14 (?).]

[Footnote 6: The identification of the "hosts" with the stars comes to the same thing; the stars were thought of as closely connected with angels. It is probable that the "hosts" were also identified with the armies of Israel.]

[Footnote 7: Rev. i. 4.]

[Footnote 8: Gen. xxxii. 30; Judges xiii. 22.]

[Footnote 9: Exod. iii. 2, xiv.]

[Footnote 10: Zech. i. 11f.]

[Footnote 11: Cf. xviii. I with xviii. 2, and note change of number in xix. 17.]

[Footnote 12: Gen. xxviii. 12, E.]

[Footnote 13: Gen. xxxii. I, E.]

[Footnote 14: Gen. xxxii. 24, 30, J.]

[Footnote 15: "An angel" of I Kings xiii. 18 might be the Mal'akh Yahweh, as in xix. 5, cf. 7, or the passage, at any rate in its present form, may be exilic or post-exilic.]

[Footnote 16: Deut. vi. 4. 5.]

[Footnote 17: Isaiah xliii. 10 &c.]

[Footnote 18: It is not however certain that these doctrines of Zoroastrianism were developed at so early a date.]

[Footnote 19: Ezek. i.x.]

[Footnote 20: Ezek. ix.]

[Footnote 21: Zech. i. 11 f.]

[Footnote 22: Zech. iii. 1.]

[Footnote 23: Job i., ii. Cf. I Chron. xxi. 1.]

[Footnote 24: Pss. xci. 11, ciii. 20 &c.]

[Footnote 25: Tobit xii. 15; Rev. viii. 2.]

[Footnote 26: Dan. viii. 16, x. 13, 20, 21.]

[Footnote 27: Tob. xii. 15.]

[Footnote 28: Job iv. 18.]

[Footnote 29: Tobit iii. 8, 17, vi. 7.]

[Footnote 30: E.g. Matt. i. 20 (to Joseph), iv. 11. (to Jesus), Luke i. 26 (to Mary), Acts xii. 7 (to Peter).]

[Footnote 31: E.g. Mark viii. 38, xiii. 27.]

[Footnote 32: Mark xii. 25.]

[Footnote 33: Luke i. 19.]

[Footnote 34: Rev. ix. 11.]

[Footnote 35: Mark iii. 22.]

[Footnote 36: Mark i. 13.]

[Footnote 37: Michael, Jude 9.]

[Footnote 38: Rom. viii. 38; Col, ii. 10.]

[Footnote 39: Col. i. 16.]

[Footnote 40: Rev. vii. 1.]

[Footnote 41: Gen. xviii. 8.]

[Footnote 42: Gen. xix. 16.]

[Footnote 43: Zech. iv. 1.]

[Footnote 44: Judges vi. 12, 21.]

[Footnote 45: Rev. vii. 1. viii.]

[Footnote 46: Rev. viii. 13, xiv. 6.]

[Footnote 47: Job xxxviii. 7; Asc. of Isaiah, iv. 18; Slav. Enoch, iv. 1.]

[Footnote 48: Rev. xiv. 18, xvi. 5; possibly Gal. iv. 3; Col. ii. 8, 20.]

[Footnote 49: Ps. lxviii. 17; Dan. vii. 10.]

[Footnote 50: Matt, xviii. 10; Acts xii. 15.]

[Footnote 51: Gal. iii. 19; Heb. ii. 2; LXX. of Deut. xxxiii. 2.]

BIBLIOGRAPHY.—See the sections on "Angels" in the handbooks of O.T. Theology by Ewald, Schultz, Smend, Kayser-Marti, &c.; and of N.T. Theology by Weiss, and in van Oosterzee's Dogmatics. Also commentaries on special passages, especially Driver and Bevan on Daniel, and G.A. Smith, Minor Prophets, ii. 310 ff.; and articles s.v. "Angel" in Hastings' Bible Dictionary, and the Encyclopaedia Biblica.

(W.H. BE.)



ANGEL, a gold coin, first used in France (angelot, ange) in 1340, and introduced into England by Edward IV. in 1465 as a new issue of the "noble," and so at first called the "angel-noble." It varied in value between that period and the time of Charles I. (when it was last coined) from 6s. 8d. to 10s. The name was derived from the representation it bore of St. Michael and the dragon. The angel was the coin given to those who came to be touched for the disease known as king's evil; after it was no longer coined, medals, called touch-pieces, with the same device, were given instead.



ANGELICA, a genus of plants of the natural order _Umbelliferae_, represented in Britain by one species, _A. sylvestris_, a tall perennial herb with large bipinnate leaves and large compound umbels of white or purple flowers. The name Angelica is popularly given to a plant of an allied genus, _Archangelica officinalis_, the tender shoots of which are used in making certain kinds of aromatic sweetmeats. _Angelica balsam_ is obtained by extracting the roots with alcohol, evaporating and extracting the residue with ether. It is of a dark brown colour and contains angelica oil, angelica wax and angelicin, C_{18}_H_{30}_O. The essential oil of the roots of _Angelica archangelica_ contains ss-terebangelene, C_{10}_H_{16}, and other terpenes; the oil of the seeds also contains ss-terebangelene, together with methylethylacetic acid and hydroxymyristic acid.

The angelica tree is a member of the order Avaliaceae, a species of Aralia (A. spinosa), a native of North America; it grows 8 to 12 ft. high, has a simple prickle-bearing stem forming an umbrella-like head, and much divided leaves.



ANGELICO, FRA (1387-1455), Italian painter. Il Beato Fra Giovanni Angelico da Fiesole is the name given to a far-famed painter-friar of the Florentine state in the 15th century, the representative, beyond all other men, of pietistic painting. He is often, but not accurately, termed simply "Fiesole," which is merely the name of the town where he first took the vows; more often Fra Angelico. If we turn his compound designation into English, it runs thus—"the Beatified Friar John the Angelic of Fiesole." In his lifetime he was known no doubt simply as Fra Giovanni or Friar John; "The Angelic" is a laudatory term which was assigned to him at an early date,—we find it in use within thirty years after his death; and, at some period which is not defined in our authorities, he was beatified by due ecclesiastical process. His baptismal name was Guido, Giovanni being only his name in religion. He was born at Vicchio, in the Tuscan province of Mugello, of unknown but seemingly well-to-do parentage, in 1387 (not 1390 as sometimes stated); in 1407 he became a novice in the convent of S. Domenico at Fiesole, and in 1408 he took the vows and entered the Dominican order. Whether he had previously been a painter by profession is not certain, but may be pronounced probable. The painter named Lorenzo Monaco may have contributed to his art-training, and the influence of the Sienese school is discernible in his work.

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According to Vasari, the first paintings of this artist were in the Certosa of Florence; none such exist there now. His earliest extant performances, in considerable number, are at Cortona, whither he was sent during his novitiate, and here apparently he spent all the opening years of his monastic life. His first works executed in fresco were probably those, now destroyed, which he painted in the convent of S. Domenico in this city; as a fresco-painter, he may have worked under, or as a follower of, Gherardo Starnina. From 1418 to 1436 he was back at Fiesole; in 1436 he was transferred to the Dominican convent of S. Marco in Florence, and in 1438 undertook to paint the altarpiece for the choir, followed by many other works; he may have studied about this time the renowned frescoes in the Brancacci chapel in the Florentine church of the Carmine and also the paintings of Orcagna. In or about 1445 he was invited by the pope to Rome. The pope who reigned from 1431 to 1447 was Eugenius IV., and he it was who in 1445 appointed another Dominican friar, a colleague of Angelico, to be archbishop of Florence. If the story (first told by Vasari) is true—that this appointment was made at the suggestion of Angelico only after the archbishopric had been offered to himself, and by him declined on the ground of his inaptitude for so elevated and responsible a station—Eugenius, and not (as stated by Vasari) his successor Nicholas V., must have been the pope who sent the invitation and made the offer to Fra Giovanni, for Nicholas only succeeded in 1447. The whole statement lacks authentication, though in itself credible enough. Certain it is that Angelico was staying in Rome in the first half of 1447; and he painted in the Vatican the Cappella del Sacramento, which was afterwards demolished by Paul III. In June 1447 he proceeded to Orvieto, to paint in the Cappella Nuova of the cathedral, with the co-operation of his pupil Benozzo Gozzoli. He afterwards returned to Rome to paint the chapel of Nicholas V. In this capital he died in 1455, and he lies buried in the church of the Minerva.

According to all the accounts which have reached us, few men on whom the distinction of beatification has been conferred could have deserved it more nobly than Fra Giovanni. He led a holy and self-denying life, shunning all advancement, and was a brother to the poor; no man ever saw him angered. He painted with unceasing diligence, treating none but sacred subjects; he never retouched or altered his work, probably with a religious feeling that such as divine providence allowed the thing to come, such it should remain. He was wont to say that he who illustrates the acts of Christ should be with Christ. It is averred that he never handled a brush without fervent prayer and he wept when he painted a Crucifixion. The Last Judgment and the Annunciation were two of the subjects he most frequently treated.

Bearing in mind the details already given as to the dates of Fra Giovanni's sojournings in various localities, the reader will be able to trace approximately the sequence of the works which we now proceed to name as among his most important productions. In Florence, in the convent of S. Marco (now converted into a national museum), a series of frescoes, beginning towards 1443; in the first cloister is the Crucifixion with St. Dominic kneeling; and the same treatment recurs on a wall near the dormitory; in the chapterhouse is a third Crucifixion, with the Virgin swooning, a composition of twenty life-sized figures—the red background, which has a strange and harsh effect, is the misdoing of some restorer; an "Annunciation," the figures of about three-fourths of life-size, in a dormitory; in the adjoining passage, the "Virgin enthroned," with four saints; on the wall of a cell, the "Coronation of the Virgin," with Saints Paul, Thomas Aquinas, Benedict, Dominic, Francis and Peter Martyr; two Dominicans welcoming Jesus, habited as a pilgrim; an "Adoration of the Magi"; the "Marys at the Sepulchre." All these works are later than the altarpiece which Angelico painted (as before mentioned) for the choir connected with this convent, and which is now in the academy of Florence; it represents the Virgin with Saints Cosmas and Damian (the patrons of the Medici family), Dominic, Peter, Francis, Mark, John Evangelist and Stephen; the pediment illustrated the lives of Cosmas and Damian, but it has long been severed from the main subject. In the Uffizi gallery, an altarpiece, the Virgin (life-sized) enthroned, with the Infant and twelve angels. In S. Domenico, Fiesole, a few frescoes, less fine than those in S. Marco; also an altarpiece in tempera of the Virgin and Child between Saints Peter, Thomas Aquinas, Dominic and Peter Martyr, now much destroyed. The subject which originally formed the predella of this picture has, since 1860, been in the National Gallery, London, and worthily represents there the hand of the saintly painter. The subject is a Glory, Christ with the banner of the Resurrection, and a multitude of saints, including, at the extremities, the saints or beati of the Dominican order; here are no fewer than 266 figures or portions of figures, many of them having names inscribed. This predella was highly lauded by Vasari; still more highly another picture which used to form an altarpiece in Fiesole, and which now obtains world-wide celebrity in the Louvre—the "Coronation of the Virgin," with eight predella subjects of the miracles of St. Dominic. For the church of Santa Trinita, Florence, Angelico executed a "Deposition from the Cross," and for the church of the Angeli, a "Last Judgment," both now in the Florentine academy; for S. Maria Novella, a "Coronation of the Virgin," with a predella in three sections, now in the Uffizi,—this again is one of his masterpieces. In Orvieto cathedral he painted three triangular divisions of the ceiling, portraying respectively Christ in a glory of angels, sixteen saints and prophets, and the virgin and apostles: all these are now much repainted and damaged. In Rome, in the Chapel of Nicholas V., the acts of Saints Stephen and Lawrence; also various figures of saints, and on the ceiling the four evangelists. These works of the painter's advanced age, which have suffered somewhat from restorations, show vigour superior to that of his youth, along with a more adequate treatment of the architectural perspectives. Naturally, there are a number of works currently attributed to Angelico, but not really his; for instance, a "St Thomas with the Madonna's girdle," in the Lateran museum, and a "Virgin enthroned," in the church of S. Girolamo, Fiesole. It has often been said that he commenced and frequently practised as an illuminator; this is dubious and a presumption arises that illuminations executed by Giovanni's brother, Benedetto, also a Dominican, who died in 1448, have been ascribed to the more famous artist. Benedetto may perhaps have assisted Giovanni in the frescoes at S. Marco, but nothing of the kind is distinctly traceable. A folio series of engravings from these paintings was published in Florence, in 1852. Along with Gozzoli already mentioned, Zanobi Strozzi and Gentile da Fabriano are named as pupils of the Beato.

We have spoken of Angelico's art as "pietistic"; this is in fact its predominant character. His visages have an air of rapt suavity, devotional fervency and beaming esoteric consciousness, which is intensely attractive to some minds and realizes beyond rivalry a particular ideal—that of ecclesiastical saintliness and detachment from secular fret and turmoil. It should not be denied that he did not always escape the pitfalls of such a method of treatment, the faces becoming sleek and prim, with a smirk of sexless religiosity which hardly eludes the artificial or even the hypocritical; on other minds, therefore, and these some of the most masculine and resolute, he produces little genuine impression. After allowing for this, Angelico should nevertheless be accepted beyond cavil as an exalted typical painter according to his own range of conceptions, consonant with his monastic calling, unsullied purity of life and exceeding devoutness. Exquisite as he is in his special mode of execution, he undoubtedly falls far short, not only of his great naturalist contemporaries such as Masaccio and Lippo Lippi, but even of so distant a precursor as Giotto, in all that pertains to bold or life-like invention of a subject or the realization of ordinary appearances, expressions and actions—the facts of nature, as distinguished from the aspirations or contemplations of the spirit. Technically speaking, he had much finish and harmony of composition and colour, without corresponding mastery of light and shade, and his knowledge of the human frame was restricted. The brilliancy and fair light scale of his tints is constantly remarkable, combined with a free use of gilding; this conduces materially to that celestial character which so pre-eminently distinguishes his pictured visions of the divine persons, the hierarchy of heaven and the glory of the redeemed.

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Books regarding Fra Angelico are numerous. We may mention those by S. Beissel, 1895; V.M. Crawford, 1900; R.L. Douglas, 1900; I.B. Supino, 1901; D. Tumiati, 1897; G. Williamson, 1901.

(W.M.R.)



ANGELL, GEORGE THORNDIKE (1823-1909), American philanthropist, was born at Southbridge, Massachusetts, on the 5th of June 1823. He graduated at Dartmouth in 1846, studied law at the Harvard Law School, and in 1851 was admitted to the bar in Boston, where he practised for many years. In 1868 he founded and became president of the Massachusetts Society for the Prevention of Cruelty to Animals, in the same year establishing and becoming editor of Our Dumb Animals, a journal for the promotion of organized effort in securing the humane treatment of animals. For many years he was active in the organization of humane societies in England and America. In 1882 he initiated the movement for the establishment of Bands of Mercy (for the promotion of humane treatment of animals), of which in 1908 there were more than 72,000 in active existence. In 1889 he founded and became president of the American Humane Education Society. He became well known as a criminologist and also as an advocate of laws for the safeguarding of the public health and against adulteration of food. He died at Boston on the 16th of March 1909.



ANGEL-LIGHTS, in architecture, the outer upper lights in a perpendicular window, next to the springing; probably a corruption of the word angle-lights, as they are nearly triangular.



ANGELUS, a Roman Catholic devotion in memory of the Annunciation. It has its name from the opening words, Angelus Domini nuntiavit Mariae. It consists of three texts describing the mystery, recited as versicle and response alternately with the salutation "Hail, Mary!" This devotion is recited in the Catholic Church three times daily, about 6 A.M., noon and 6 P.M. At these hours a bell known as the Angelus bell is rung. This is still rung in some English country churches, and has often been mistaken for and alleged to be a survival of the curfew bell. The institution of the Angelus is by some ascribed to Pope Urban II., by some to John XXII. The triple recitation is ascribed to Louis XI. of France, who in 1472 ordered it to be thrice said daily.



ANGELUS SILESIUS (1624-1677), German religious poet, was born in 1624 at Breslau. His family name was Johann Scheffler, but he is generally known by the pseudonym Angelus Silesius, under which he published his poems and which marks the country of his birth. Brought up a Lutheran, and at first physician to the duke of Wuerttemberg-Oels, he joined in 1652 the Roman Catholic Church, in 1661 took orders as a priest, and became coadjutor to the prince bishop of Breslau. He died at Breslau on the 9th of July 1677. In 1657 Silesius published under the title Heilige Seelenlust, oder geistliche Hirtenlieder der in ihren Jesum verliebten Psyche (1657), a collection of 205 hymns, the most beautiful of which, such as, Liebe, die du mich zum Bilde deiner Gottheit hast gemacht and Mir nach, spricht Christus, unser Held, have been adopted in the German Protestant hymnal. More remarkable, however, is his Geistreiche Sinn-und Schluss-reime (1657), afterwards called Cherubinischer Wandersmann (1674). This is a collection of "Reimsprueche" or rhymed distichs embodying a strange mystical pantheism drawn mainly from the writings of Jakob Boehme and his followers. Silesius delighted specially in the subtle paradoxes of mysticism. The essence of God, for instance, he held to be love; God, he said, can love nothing inferior to himself; but he cannot be an object of love to himself without going out, so to speak, of himself, without manifesting his infinity in a finite form; in other words, by becoming man. God and man are therefore essentially one.

A complete edition of Scheffler's works (Saemtliche poetische Werke) was published by D.A. Rosenthal, 2 vols. (Regensburg, 1862). Both the Cherubinischer Wandersmann and Heilige Seelenlust have been republished by G. Ellinger (1895 and 1901); a selection from the former work by O.E. Hartleben (1896). For further notices of Silesius' life and work, see Hoffmann von Fallersleben in Weimarisches Jahrbuch I. (Hanover, 1854); A. Kahlert, Angelus Silesius (1853); C. Seltmann, Angelus Silesius und seine Mystik (1896), and a biog. by H. Mahn (Dresden, 1896).



ANGERMUeNDE, a town of Germany, in the Prussian province of Brandenburg, on Lake Muende, 43 m. from Berlin by the Berlin-Stettin railway, and at the junction of lines to Prenzlau, Freien-walde and Schwedt. Pop. (1900) 7465. It has three Protestant churches, a grammar school and court of law. Its industries embrace iron founding and enamel working. In 1420 the elector Frederick I. of Brandenburg gained here a signal victory over the Pomeranians.



ANGERONA, or ANGERONIA, an old Roman goddess, whose name and functions are variously explained. According to ancient authorities, she was a goddess who relieved men from pain and sorrow, or delivered the Romans and their flocks from angina (quinsy); or she was the protecting goddess of Rome and the keeper of the sacred name of the city, which might not be pronounced lest it should be revealed to her enemies; it was even thought that Angerona itself was this name. Modern scholars regard her as a goddess akin to Ops, Acca Larentia and Dea Dia; or as the goddess of the new year and the returning sun (according to Mommsen, ab angerendo= [Greek: apo tou anapheresthai. ton haelion).] Her festival, called Divalia or Angeronalia, was celebrated on the 21st of December. The priests offered sacrifice in the temple of Volupia, the goddess of pleasure, in which stood a statue of Angerona, with a finger on her mouth, which was bound and closed (Macrobius i. 10; Pliny, Nat. Hist. iii. 9; Varro, L. L. vi. 23). She was worshipped as Ancharia at Faesulae, where an altar belonging to her has been recently discovered. (See FAESULAE.)



ANGERS, a city of western France, capital of the department of Maine-et-Loire, 191 m. S.W. of Paris by the Western railway to Nantes. Pop. (1906) 73,585. It occupies rising ground on both banks of the Maine, which are united by three bridges. The surrounding district is famous for its flourishing nurseries and market gardens. Pierced with wide, straight streets, well provided with public gardens, and surrounded by ample, tree-lined boulevards, beyond which lie new suburbs, Angers is one of the pleasantest towns in France. Of its numerous medieval buildings the most important is the cathedral of St. Maurice, dating in the main from the 12th and 13th centuries. Between the two flanking towers of the west facade, the spires of which are of the 16th century, rises a central tower of the same period. The most prominent feature of the facade is the series of eight warriors carved on the base of this tower. The vaulting of the nave takes the form of a series of cupolas, and that of the choir and transept is similar. The chief treasures of the church are its rich stained glass (12th, 13th and 15th centuries) and valuable tapestry (14th to 18th centuries). The bishop's palace which adjoins the cathedral contains a fine synodal hall of the 12th century. Of the other churches of Angers, the principal are St. Serge, an abbey-church of the 12th and 15th centuries, and La Trinite (12th century). The prefecture occupies the buildings of the famous abbey of St. Aubin; in its courtyard are elaborately sculptured arcades of the 11th and 12th centuries, from which period dates the tower, the only survival of the splendid abbey-church. Ruins of the old churches of Toussaint (13th century) and Notre-Dame du Ronceray (11th century) are also to be seen. The castle of Angers, an imposing building girt with towers and a moat, dates from the 13th century and is now used as an armoury. The ancient hospital of St. Jean (12th century) is occupied by an archaeological museum; and the Logis Barrault, a mansion built about 1500, contains the public library, the municipal museum, which has a large collection of pictures and sculptures, and the Musee David, containing works by the famous sculptor David d'Angers, who was a native of the town. One of his masterpieces, a bronze statue of Rene of Anjou, stands close by the castle. The Hotel de Pince or d'Anjou (1523-1530) is the finest of the stone mansions of Angers; there are also many curious wooden houses of the 15th and 16th centuries. The palais de justice, the Catholic institute, a fine theatre, and a hospital with 1500 beds are the more remarkable of the modern buildings of the town. Angers is the seat of a bishopric, dating from the 3rd century, a prefecture, a court of appeal and a court of assizes. It has a tribunal of first instance, a tribunal of commerce, a board of trade-arbitrators, a chamber of commerce, a branch of the Bank of France and several learned societies. Its educational institutions include ecclesiastical seminaries, a lycee, a preparatory school of medicine and pharmacy, a university with free faculties (facultes libres) of theology, law, letters and science, a higher school of agriculture, training colleges, a school of arts and handicrafts and a school of fine art. The prosperity of the town is largely due to the great slate-quarries of the vicinity, but the distillation of liqueurs from fruit, cable, rope and thread-making, and the manufacture of boots and shoes, umbrellas and parasols are leading industries. The weaving of sail-cloth and woollen and other fabrics, machine construction, wire-drawing, and manufacture of sparkling wines and preserved fruits are also carried on. The chief articles of commerce, besides slate and manufactured goods, are hemp, early vegetables, fruit, flowers and live-stock.

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Angers, capital of the Gallic tribe of the Andecavi, was under the Romans called Juliomagus. During the 9th century it became the seat of the counts of Anjou (q.v.). It suffered severely from the invasions of the Northmen in 845 and the succeeding years, and of the English in the 12th and 15th centuries; the Huguenots took it in 1585, and the Vendean royalists were repulsed near it in 1793. Till the Revolution, Angers was the seat of a celebrated university founded in the 14th century.

See L.M. Thorode, Notice de la ville d'Angers (Angers, 1897).



ANGERSTEIN, JOHN JULIUS (1735-1822), London merchant, and patron of the fine arts, was born at St. Petersburg and settled in London about 1749. His collection of paintings, consisting of about forty of the most exquisite specimens of the art, purchased by the British government, on his death, formed the nucleus of the National Gallery.



ANGILBERT (d. 814), Frankish Latin poet, and minister of Charlemagne, was of noble Frankish parentage, and educated at the palace school under Alcuin. As the friend and adviser of the emperor's son, Pippin, he assisted for a while in the government of Italy, and was later sent on three important embassies to the pope, in 792, 794 and 796. Although he was the father of two children by Charlemagne's daughter, Bertha, one of them named Nithard, we have no authentic account of his marriage, and from 790 he was abbot of St. Riquier, where his brilliant rule gained for him later the renown of a saint. Angilbert, however, was little like the true medieval saint; his poems reveal rather the culture and tastes of a man of the world, enjoying the closest intimacy with the imperial family. He accompanied Charlemagne to Rome in 800 and was one of the witnesses to his will in 814. Angilbert was the Homer of the emperor's literary circle, and was the probable author of an epic, of which the fragment which has been preserved describes the life at the palace and the meeting between Charlemagne and Leo III. It is a mosaic from Virgil, Ovid, Lucan and Fortunatus, composed in the manner of Einhard's use of Suetonius, and exhibits a true poetic gift. Of the shorter poems, besides the greeting to Pippin on his return from the campaign against the Avars (796), an epistle to David (Charlemagne) incidentally reveals a delightful picture of the poet living with his children in a house surrounded by pleasant gardens near the emperor's palace. The reference to Bertha, however, is distant and respectful, her name occurring merely on the list of princesses to whom he sends his salutation.

Angilbert's poems have been published by E. Dummler in the Monumenta Germaniae Historica. For criticisms of this edition see Traube in Roederer's Schriften fuer germanische Philologie (1888). See also A. Molinier, Les Sources de l'histoire de France.



ANGINA PECTORIS (Latin for "pain of the chest"), a term applied to a violent paroxysm of pain, arising almost invariably in connexion with disease of the coronary arteries, a lesion causing progressive degeneration of the heart muscle (see HEART: Disease). An attack of angina pectoris usually comes on with a sudden seizure of pain, felt at first over the region of the heart, but radiating through the chest in various directions, and frequently extending down the left arm. A feeling of constriction and of suffocation accompanies the pain, although there is seldom actual difficulty in breathing. When the attack comes on, as it often does, in the course of some bodily exertion, the sufferer is at once brought to rest, and during the continuance of the paroxysm experiences the most intense agony. The countenance becomes pale, the surface of the body cold, the pulse feeble, and death appears to be imminent, when suddenly the attack subsides and complete relief is obtained. The duration of a paroxysm rarely exceeds two or three minutes, but it may last for a longer period. The attacks are apt to recur on slight exertion, and even in aggravated cases without any such exciting cause. Occasionally the first seizure proves fatal; but more commonly death takes place as the result of repeated attacks. Angina pectoris is extremely rare under middle life, and is much more common in males than in females. It must always be regarded as a disorder of a very serious nature. In the treatment of the paroxysm, nitrite of amyl has now replaced all other remedies. It can be carried by the patient in the form of nitrite of amyl pearls, each pearl containing the dose prescribed by the physician. Kept in this way the drug does not lose strength. As soon as the pain begins the patient crushes a pearl in his handkerchief and holds it to his mouth and nose. The relief given in this way is marvellous and usually takes place within a very few seconds. In the rare cases where this drug does not relieve, hypodermic injections of morphia are used. But on account of the well-known dangers of this drug, it should only be administered by a medical man. To prevent recurrence of the attacks something may be done by scrupulous attention to the general health, and by the avoidance of mental and physical strain. But the most important preventive of all is "bed," of which fourteen days must be enforced on the least premonition of anginal pain.

Pseudo-angina.—In connexion with angina pectoris, a far more common condition must be mentioned that has now universally received the name of pseudo-angina. This includes the praecordial pains which very closely resemble those of true angina. The essential difference lies in the fact that pseudo-angina is independent of structural disease of the heart and coronary arteries. In true angina there is some condition within the heart which starts the stimulus sent to the nerve centres. In pseudo-angina the starting-point is not the heart but some peripheral or visceral nerve. The impulse passes thence to the medulla, and so reaching the sensory centres starts a feeling of pain that radiates into the chest or down the arm. There are three main varieties:—(1) the reflex, (2) the vaso-motor, (3) the toxic. The reflex is by far the most common, and is generally due to irritation from one of the abdominal organs. An attack of pseudo-angina may be agonizing, the pain radiating through the chest and into the left arm, but the patient does not usually assume the motionless attitude of true angina, and the duration of the seizure is usually much longer. The treatment is that of the underlying neurosis and the prognosis is a good one, sudden death not occurring.



ANGIOSPERMS. The botanical term "Angiosperm" ([Greek: angeion], receptacle, and [Greek: sperma], seed) was coined in the form Angiospermae by Paul Hermann in 1690, as the name of that one of his primary divisions of the plant kingdom, which included flowering plants possessing seeds enclosed in capsules, in contradistinction to his Gymnospermae, or flowering plants with achenial or schizo-carpic fruits—the whole fruit or each of its pieces being here regarded as a seed and naked. The term and its antonym were maintained by Linnaeus with the same sense, but with restricted application, in the names of the orders of his class Didynamia. Its use with any approach to its modern scope only became possible after Robert Brown had established in 1827 the existence of truly naked seeds in the Cycadeae and Coniferae, entitling them to be correctly called Gymnosperms. From that time onwards, so long as these Gymnosperms were, as was usual, reckoned as dicotyledonous flowering plants, the term Angiosperm was used antithetically by botanical writers, but with varying limitation, as a group-name for other dicotyledonous plants. The advent in 1851 of Hofmeister's brilliant discovery of the changes proceeding in the embryo-sac of flowering plants, and his determination of the correct relationships of these with the Cryptogamia, fixed the true position of Gymnosperms as a class distinct from Dicotyledons, and the term Angiosperm then gradually came to be accepted as the suitable designation for the whole of the flowering plants other than Gymnosperms, and as including therefore the classes of Dicotyledons and Monocotyledons. This is the sense in which the term is nowadays received and in which it is used here.

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The trend of the evolution of the plant kingdom has been in the direction of the establishment of a vegetation of fixed habit and adapted to the vicissitudes of a life on land, and the Angiosperms are the highest expression of this evolution and constitute the dominant vegetation of the earth's surface at the present epoch. There is no land-area from the poles to the equator, where plant-life is possible, upon which Angiosperms are not found. They occur also abundantly in the shallows of rivers and fresh-water lakes, and in less number in salt lakes and in the sea; such aquatic Angiosperms are not, however, primitive forms, but are derived from immediate land-ancestors. Associated with this diversity of habitat is great variety in general form and manner of growth. The familiar duckweed which covers the surface of a pond consists of a tiny green "thalloid" shoot, one, that is, which shows no distinction of parts—stem and leaf, and a simple root growing vertically downwards into the water. The great forest-tree has a shoot, which in the course perhaps of hundreds of years, has developed a wide-spreading system of trunk and branches, bearing on the ultimate twigs or branchlets innumerable leaves, while beneath the soil a widely-branching root-system covers an area of corresponding extent. Between these two extremes is every conceivable gradation, embracing aquatic and terrestrial herbs, creeping, erect or climbing in habit, shrubs and trees, and representing a much greater variety than is to be found in the other subdivision of seed-plants, the Gymnosperms.

Internal structure.

In internal structure also the variety of tissue-formation far exceeds that found in Gymnosperms (see PLANTS: Anatomy). The vascular bundles of the stem belong to the collateral type, that is to say, the elements of the wood or xylem and the bast or phloem stand side by side on the same radius. In the larger of the two great groups into which the Angiosperms are divided, the Dicotyledons, the bundles in the very young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue, known as cambium; by the formation of a layer of cambium between the bundles (interfascicular cambium) a complete ring is formed, and a regular periodical increase in thickness results from it by the development of xylem on the inside and phloem on the outside. The soft phloem soon becomes crushed, but the hard wood persists, and forms the great bulk of the stem and branches of the woody perennial. Owing to differences in the character of the elements produced at the beginning and end of the season, the wood is marked out in transverse section into concentric rings, one for each season of growth—the so-called annual rings. In the smaller group, the Monocotyledons, the bundles are more numerous in the young stem and scattered through the ground tissue. Moreover they contain no cambium and the stem once formed increases in diameter only in exceptional cases.

Vegetative organs.

As in Gymnosperms, branching is monopodial; dichotomy or the forking of the growing point into two equivalent branches which replace the main stem, is absent both in the case of the stem and the root. The leaves show a remarkable variety in form (see LEAF), but are generally small in comparison with the size of the plant; exceptions occur in some Monocotyledons, e.g. in the Aroid family, where in some genera the plant produces one huge, much-branched leaf each season.

In rare cases the main axis is unbranched and ends in a flower, as, for instance, in the tulip, where scale-leaves, forming the underground bulb, green foliage-leaves and coloured floral leaves are borne on one and the same axis. Generally, flowers are formed only on shoots of a higher order, often only on the ultimate branches of a much branched system. A potential branch or bud, either foliage or flower, is formed in the axil of each leaf; sometimes more than one bud arises, as for instance in the walnut, where two or three stand in vertical series above each leaf. Many of the buds remain dormant, or are called to development under exceptional circumstances, such as the destruction of existing branches. For instance, the clipping of a hedge or the lopping of a tree will cause to develop numerous buds which may have been dormant for years. Leaf-buds occasionally arise from the roots, when they are called adventitious; this occurs in many fruit trees, poplars, elms and others. For instance, the young shoots seen springing from the ground around an elm are not seedlings but root-shoots. Frequently, as in many Dicotyledons, the primary root, the original root of the seedling, persists throughout the life of the plant, forming, as often in biennials, a thickened tap-root, as in carrot, or in perennials, a much-branched root system. In many Dicotyledons and most Monocotyledons, the primary root soon perishes, and its place is taken by adventitious roots developed from the stem.

Flower.

The most characteristic feature of the Angiosperm is the flower, which shows remarkable variety in form and elaboration, and supplies the most trustworthy characters for the distinction of the series and families or natural orders, into which the group is divided. The flower is a shoot (stem bearing leaves) which has a special form associated with the special function of ensuring the fertilization of the egg and the development of fruit containing seed. Except where it is terminal it arises, like the leaf-shoot, in the axil of a leaf, which is then known as a bract. Occasionally, as in violet, a flower arises singly in the axil of an ordinary foliage-leaf; it is then termed axillary. Generally, however, the flower-bearing portion of the plant is sharply distinguished from the foliage leaf-bearing or vegetative portion, and forms a more or less elaborate branch-system in which the bracts are small and scale-like. Such a branch-system is called an inflorescence. The primary function of the flower is to bear the spores. These, as in Gymnosperms, are of two kinds, microspores or pollen-grains, borne in the stamens (or microsporophylls) and megaspores, in which the egg-cell is developed, contained in the ovule, which is borne enclosed in the carpel (or megasporophyll). The flower may consist only of spore-bearing leaves, as in willow, where each flower comprises only a few stamens or two carpels. Usually, however, other leaves are present which are only indirectly concerned with the reproductive process, acting as protective organs for the sporophylls or forming an attractive envelope. These form the perianth and are in one series, when the flower is termed monochlamydeous, or in two series (dichlamydeous). In the second case the outer series (calyx of sepals) is generally green and leaf-like, its function being to protect the rest of the flower, especially in the bud; while the inner series (corolla of petals) is generally white or brightly coloured, and more delicate in structure, its function being to attract the particular insect or bird by agency of which pollination is effected. The insect, &c., is attracted by the colour and scent of the flower, and frequently also by honey which is secreted in some part of the flower. (For further details on the form and arrangement of the flower and its parts, see FLOWER.)

Stamen and pollen.

Each stamen generally bears four pollen-sacs (microsporangia) which are associated to form the anther, and carried up on a stalk or filament. The development of the microsporangia and the contained spores (pollen-grains) is closely comparable with that of the microsporangia in Gymnosperms or heterosporous ferns. The pollen is set free by the opening (dehiscence) of the anther, generally by means of longitudinal slits, but sometimes by pores, as in the heath family (Ericaceae), or by valves, as in the barberry. It is then dropped or carried by some external agent, wind, water or some member of the animal kingdom, on to the receptive surface of the carpel of the same or another flower. The carpel, or aggregate of carpels forming the pistil or gynaeceum, comprises an ovary containing one or more ovules and a receptive surface or stigma; the stigma is sometimes carried up on a style. The mature pollen-grain is, like other spores, a single cell; except in the case of some submerged aquatic plants, it has a double wall, a thin delicate wall of unaltered cellulose, the endospore or intine, and a tough outer cuticularized exospore or extine. The exospore often bears spines or warts, or is variously sculptured, and the character of the markings is often of value for the distinction of genera or higher groups. Germination of the microspore begins before it leaves the pollen-sac. In very few cases has anything representing prothallial development been observed; generally a small cell (the antheridial or generative cell) is cut off, leaving a larger tube-cell. When placed on the stigma, under favourable circumstances, the pollen-grain puts forth a pollen-tube which grows down the tissue of the style to the ovary, and makes its way along the placenta, guided by projections or hairs, to the mouth of an ovule. The nucleus of the tube-cell has meanwhile passed into the tube, as does also the generative nucleus which divides to form two male- or sperm-cells. The male-cells are carried to their destination in the tip of the pollen-tube.

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Pistil and embryo-sac.

The ovary contains one or more ovules borne on a placenta, which is generally some part of the ovary-wall. The development of the ovule, which represents the macrosporangium, is very similar to the process in Gymnosperms; when mature it consists of one or two coats surrounding the central nucellus, except at the apex where an opening, the micropyle, is left. The nucellus is a cellular tissue enveloping one large cell, the embryo-sac or macrospore. The germination of the macrospore consists in the repeated division of its nucleus to form two groups of four, one group at each end of the embryo-sac. One nucleus from each group, the polar nucleus, passes to the centre of the sac, where the two fuse to form the so-called definitive nucleus. Of the three cells at the micropylar end of the sac, all naked cells (the so-called egg-apparatus), one is the egg-cell or oosphere, the other two, which may be regarded as representing abortive egg-cells (in rare cases capable of fertilization), are known as synergidae. The three cells at the opposite end are known as antipodal cells and become invested with a cell-wall. The gametophyte or prothallial generation is thus extremely reduced, consisting of but little more than the male and female sexual cells—the two sperm-cells in the pollen-tube and the egg-cell (with the synergidae) in the embryo-sac.

Fertilization.

At the period of fertilization the embryo-sac lies in close proximity to the opening of the micropyle, into which the pollen-tube has penetrated, the separating cell-wall becomes absorbed, and the male or sperm-cells are ejected into the embryo-sac. Guided by the synergidae one male-cell passes into the oosphere with which it fuses, the two nuclei uniting, while the other fuses with the definitive nucleus, or, as it is also called, the endosperm nucleus. This remarkable double fertilization as it has been called, although only recently discovered, has been proved to take place in widely-separated families, and both in Monocotyledons and Dicotyledons, and there is every probability that, perhaps with variations, it is the normal process in Angiosperms. After impregnation the fertilized oosphere immediately surrounds itself with a cell-wall and becomes the oospore which by a process of growth forms the embryo of the new plant. The endosperm-nucleus divides rapidly to produce a cellular tissue which fills up the interior of the rapidly-growing embryo-sac, and forms a tissue, known as endosperm, in which is stored a supply of nourishment for the use later on of the embryo. It has long been known that after fertilization of the egg has taken place, the formation of endosperm begins from the endosperm nucleus, and this had come to be regarded as the recommencement of the development of a prothallium after a pause following the reinvigorating union of the polar nuclei. This view is still maintained by those who differentiate two acts of fertilization within the embryo-sac, and regard that of the egg by the first male-cell, as the true or generative fertilization, and that of the polar nuclei by the second male gamete as a vegetative fertilization which gives a stimulus to development in correlation with the other. If, on the other hand, the endosperm is the product of an act of fertilization as definite as that giving rise to the embryo itself, we have to recognize that twin-plants are produced within the embryo-sac—one, the embryo, which becomes the angiospermous plant, the other, the endosperm, a short-lived, undifferentiated nurse to assist in the nutrition of the former, even as the subsidiary embryos in a pluri-embryonic Gymnosperm may facilitate the nutrition of the dominant one. If this is so, and the endosperm like the embryo is normally the product of a sexual act, hybridization will give a hybrid endosperm as it does a hybrid embryo, and herein (it is suggested) we may have the explanation of the phenomenon of xenia observed in the mixed endosperms of hybrid races of maize and other plants, regarding which it has only been possible hitherto to assert that they were indications of the extension of the influence of the pollen beyond the egg and its product. This would not, however, explain the formation of fruits intermediate in size and colour between those of crossed parents. The signification of the coalescence of the polar nuclei is not explained by these new facts, but it is noteworthy that the second male-cell is said to unite sometimes with the apical polar nucleus, the sister of the egg, before the union of this with the basal polar one. The idea of the endosperm as a second subsidiary plant is no new one; it was suggested long ago in explanation of the coalescence of the polar nuclei, but it was then based on the assumption that these represented male and female cells, an assumption for which there was no evidence and which was inherently improbable. The proof of a coalescence of the second male nucleus with the definitive nucleus gives the conception a more stable basis. The antipodal cells aid more or less in the process of nutrition of the developing embryo, and may undergo multiplication, though they ultimately disintegrate, as do also the synergidae. As in Gymnosperms and other groups an interesting qualitative change is associated with the process of fertilization. The number of chromosomes (see PLANTS: Cytology) in the nucleus of the two spores, pollen-grain and embryo-sac, is only half the number found in an ordinary vegetative nucleus; and this reduced number persists in the cells derived from them. The full number is restored in the fusion of the male and female nuclei in the process of fertilization, and remains until the formation of the cells from which the spores are derived in the new generation.

In several natural orders and genera departures from the course of development just described have been noted. In the natural order Rosaceae, the series Querciflorae, and the very anomalous genus Casuarina and others, instead of a single macrospore a more or less extensive sporogenous tissue is formed, but only one cell proceeds to the formation of a functional female cell. In Casuarina, Juglans and the order Corylaceae, the pollen-tube does not enter by means of the micropyle, but passing down the ovary wall and through the placenta, enters at the chalazal end of the ovule. Such a method of entrance is styled chalazogamic, in contrast to the porogamic or ordinary method of approach by means of the micropyle.

Embryology.

The result of fertilization is the development of the ovule into the seed. By the segmentation of the fertilized egg, now invested by cell-membrane, the embryo-plant arises. A varying number of transverse segment-walls transform it into a pro-embryo—a cellular row of which the cell nearest the micropyle becomes attached to the apex of the embryo-sac, and thus fixes the position of the developing embryo, while the terminal cell is projected into its cavity. In Dicotyledons the shoot of the embryo is wholly derived from the terminal cell of the pro-embryo, from the next cell the root arises, and the remaining ones form the suspensor. In many Monocotyledons the terminal cell forms the cotyledonary portion alone of the shoot of the embryo, its axial part and the root being derived from the adjacent cell; the cotyledon is thus a terminal structure and the apex of the primary stem a lateral one—a condition in marked contrast with that of the Dicotyledons. In some Monocotyledons, however, the cotyledon is not really terminal. The primary root of the embryo in all Angiosperms points towards the micropyle. The developing embryo at the end of the suspensor grows out to a varying extent into the forming endosperm, from which by surface absorption it derives good material for growth; at the same time the suspensor plays a direct part as a carrier of nutrition, and may even develop, where perhaps no endosperm is formed, special absorptive "suspensor roots" which invest the developing embryo, or pass out into the body and coats of the ovule, or even into the placenta. In some cases the embryo or the embryo-sac sends out suckers into the nucellus and ovular integument. As the embryo develops it may absorb all the food material available, and store, either in its cotyledons or in its hypocotyl, what is not immediately required for growth, as reserve-food for use in germination, and by so doing it increases in size until it may fill entirely the embryo-sac; or its absorptive power at this stage may be limited to what is necessary for growth and it remains of relatively small size, occupying but a small area of the embryo-sac, which is otherwise filled with endosperm in which the reserve-food is stored. There are also intermediate states. The position of the embryo in relation to the endosperm varies, sometimes it is internal, sometimes external, but the significance of this has not yet been established.

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