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Oswald BARRON, F.S.A.
Editor of . The Ancestor, 1902-1905. Hon. Genealogist to Standing Council of Arms and Armours
Honourable Society of Baronetage. English.

OSCAR BRILIANT. {Austria: Statistics.

PAUL DANIEL ALPHANDéRY. -
Professor of the History of Dogma, École Pratique des Hautes Études, Sorbonne, Apostolici;
# Author of Les Idées morales chez les hétérodoxes latines au début du XIII* l Arnold of Brescia.
stocic.

PRINCE PETER ALExEnvitch KRoPotKIN. { Aral; Astrakhan,
See the biographical article: KRopotkin, PRINce Peter A.

PETER CHALMERs MITCHELL, F.R.S., F.Z.S., D.Sc., LL.D.
Secretary to the Zoological Society of London from 1903. University Demon- || Animal;
strator in Comparative Anatomy and Assistant to Linacre Professor at Oxford, Annella
1888-1891. Lecturer on £ at Charing Cross Hospital, 1892-1894; at London •
Hospital, 1894. Examiner in Biology to the Royal College of Physicians, 1892–
# 1901-1903. Examiner in Zoology to the University £ London, 1903.
Anglesey, 1st Earl of;
Anne, Queen;
C Y M.A. Anne of Cleves;
Parlip Chesney YoRKE, M.A. Anne of Denmark:
Magdalen College, Oxford. Antrim, 1st Marquess of:
Argyll, Earls and Dukes of;

Arlington, Earl of.
PERCY GARDNER, LITT.D., LL.D.
See the biographical article: GARDNeR, Percy. Apelles.

PETER GILEs, M.A., LITT.D., LL.D.
Fellow and Classical Lecturer of Emmanuel College, Cambridge, and University + Aryan.
Reader in Comparative Philology. Author of Manual of Comparative Philology.

PHILIP LAKE, M.A., F.G.S. #:

Asia: Geology;
Austria; Geology.

Lecturer on Physical and Regional Ge' in Cambridge University. Formerly
of the Geological Survey of India. uthor of Monograph of British Cambrian
Trilobites. Translator and editor of Kayser's Comparative Geology.
PAUL WINoGRADoFF, D.C.L. (Oxford), LL.D. "' and Harvard).
Corpus Professor of Jurisprudence in the University of Qxford. Fellow, of the Anglo-Saxon Law.
British Academy. Honorary Professor of History in the University of Moscow.
Author of Villainage in England; English Society in the 11th Century, &c.
THE RIGHT Hon. LoRD RAYLEIGH. { Argon.
See the biographical article: RAYLEIGH, 3RD BARON.

RoBERT ALExANDER STEwART MACALISTER, M.A., F.S.A. Ascalon.
Director of Excavations for the Palestine Exploration Fund.

CoLoNEL RoBERT ALExANDER WAHAB, C.M.G., C. I. E. {

Served in the A# War, 1878–1880; with the Hazara Expeditions, 1888 and Arabia: Modern History;

1891; with the Tirah Expeditionary Force, 1897-1898, &c. Commissioner for Asir. the Aden Boundary £ ry SIR RICHARD CLAVERHoUSE JEBB, LL.D., D.C.L. See the biographical article: jean, Sir Richarn c. {Aristophants RICHARD GARNETT, LL.D. See the biographical article: GARNETT, Richard. {Anthology, Apotheosis, REv. RoBERT HENRY CHARLEs, M.A., D.D., LITT.D. (Oxon.). £ ": and # # £ # 9: F# of the British Apocalyptic Literature; cademy. rofessor ol Biblical Creek at Trinit ollege, Dublin, 1898-1906. terature. #c:#,£" " 98-1906. Apocryphal Literat

REGINALD INNES Pocock, F.Z.S., F.L.S.
Superintendent of the zoological Gardens, London. {Ant-lion; Aphides.

RoNALD JoHN McNEILL, M.A. - - -
Christ Church, Oxford. Formerly Editor of the St James's Gazette (London). { Australia: Recent Legislation.

RICHARD LYDEKKER, F.R.S., F.G.S., F.Z.S.
Author of Catalogues of Fossil Mammals, Reptiles and Birds in British Museum;
The Deer of all Lands; &c. Artiodactyla, Aurochs.

RB v. RoBERT MACKINTosh, M.A., D.D. Anthropomorphism; Apolo-
Professor at Lancashire Independent College, Manchester. getics; Apotheosis(in part).

RoBERT NISBET BAIN (d. 1909). Anne, Empress of Russia;
Assistant Librarian, British Museum, 1883-1909. Author of Scandinavia: the Apraksin, T. M.;
Political History of Denmark, Norway and Sweden, 1533-1900; The First Romanovs, - Arakcheev, A. A., Count;
1613 to 1725; £ Europe: the Political History of Poland and Russia from 1469 Arany, Janos;
to 1796; &c. * *

Armfelt, G. M., Count.

RALPH NICHOLsoN WoRNUM (1812-1877). - -

Keeper of the National Gallery, 1854-1877. Author of The Epochs of Painting; &c. { Arabesque.

R. PHEN# SPIERs, F.S.A., F.R.I.B.A. Apse;
Formerly Master of the Architectural School, Royal Academy; London, Past || Arcade:
President of Architectural Association. Associate and Fellow of King's College, :-
London. Corresponding Member of the Institute of France. Editor of Fergusson's *
History of Architecture. Author of Architecture: East and West; &c. Architecture.

Antelope; Arsinoltherium;

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RENé PouPARDIN, D.-8s-L.
Secretary of the École des Chartes. Honorary Librarian at the Bibliothèque | Arles, Kingdom of.
Nationale, Paris.

LIEUT.-GEN. SIR RICHARD STRACHEY, R.E., G.C.S.I., LL.D., F.R.S. Asia: Climate, Flora and
See the biographical article: St RAcHEY, SIR R. Fauna.
RoBERT SEYMoUR CoNwAY, M.A., D.LITT. (Cantab.).
Frofessor of Latin in the University of Manchester. Formerly Professor of Latin Apulia: Archaeology;
in University College, Cardiff. £ of Gonville and Caius College, Cambridge. Aricini; Aurunci.
Author of Italic Dialects. -

Fellow and Lecturer in Classics, Worcester College, Oxford. Formerly Scholar
of Christ Church, Oxford.

STANLEY ARTHUR Cook, M.A.
Editor for Palestine Exploration Fund. Formerly Fellow and Lecturer in Hebrew Ark;
and Syriac, Gonville, and Caius College, Cambridge. Examiner in Hebrew and Asa;
Aramaic, London University, 1904-1908; Council of Royal Asiatic Society, Asher;
1904-1 # Author of Glossary of Aramaic Inscriptions; The Laws of Moses and Astarte
# # £" ; Critical Notes on Old Testament History; Religion of Ancient
alestine, &c.

RotAND TRUSLovE, M.A. { Arles.

SIDNEY Colvin, M.A., D.LITT. { Art
See the biographical article: Colvin, SIDNEY. -

SIMON NEwcoMB, LL.D., D.Sc., D.C.L. (Oxon.). Astronomy: Descriptive"
See the biographical article: NEwcomb, SIMON. Astrophysics.

Viscount St Cyres. - -
See the biographical article: IDDESLEIGH, 1st EARL of. {Amania: Family.

THE RIGHT HoN. LoRD SwAYTHLING (SIR SAMUEL MonTAGU).
M.P. for Whitechapel, 1885-1900. Founder of the firm of Samuel Montagu & Co., + Arbitrage.
Bankers, London.

TIMOTHY AUGUSTINE CoGHLAN. I.S.O.
Agent-General for New South Wales. President of Australasian Association for the Australia.
Advancement of Science (Economics and Statistics), #. Author of The Seven
Colonies of Australia; Statistical Account of Australia and New Zealand.

THOMAS ALLAN INGRAM, M.A., LL.D. {Asima".

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Campagna; &c.

Ateste; Aufidena;
Augusta (Sicily);
Augusta Bagiennorum;
Augusta Praetoria Salassorums
Aurelia, Via.
Angary;
Annexation.
Asylum, Right 01.

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.

THOMAS CASE, M.A.
President of Corpus Christi College, Oxford. Formerly Waynflete Professor of Moral
and Metaphysical Philosophy at Oxford. Author of Physical Realism; &c.

THOMAS HoDGKIN, LL.D., D.LITT.
See the biographical article: HoDGKIN, T.

|-
Col. SIR THoMAs HUNGERFord Holdich, K.C.M.G., K.C.I.E., D.Sc., : Asia: Geography and

Attila.

Superintendent, Frontier Surveys, India, 1892–1898. Author of The Indian
Borderland; The Countries of the King's Award, &c. Ethnology
Anthemius;
Apollonius of Pergas

SIR THOMAS LITTLE HEATH, K.C.B., D.Sc. £).
Archimedes.

Assistant Secretary to the Treasury. Formerly Fellow of Trinity College, Cambridge.

Rev. Thomas MARTIN LINDSAY, LL.D., D.D.
Principal of the United Free Church College, Glasgow. Formerly Assistant to the
Professor of Logic and Metaphysics in the University of Edinburgh. Author of
History of the Reformation; # of Luther; &c.

WALTER THEODoRE WArts-DUNton. { Arn tthew.
See the biographical article: WATTs-DUNToN, W. T. old, Ma

Aquinas, Thomas,

T. W. RHYs DAVIDs, M.A., PH.D., LL.D. -
Professor of Comparative Religion in the University of Manchester. President of . Asoka.
the Pali, Text Society. Fellow of the British Academy. Secretary and Librarian
of Royal Asiatic Society, 1885-1902. Author of Buddhism: &c.

W. A. B. C. REv. WILLIAMAUGUSTUs BREvoorT Coolidge, M.A., F.R.G.S., HoN. PH.D. (Bern). ( Annecy;
Fellow of Magdalen College, Oxford. Professor of English History, St David's Antibes;
College, Lampeter, 1880-1881, Author of Guide du haut dauphiné; The Range of Appen in:
the Tödi, Guide to Grindelwald; Guide to Switzerland; The Alps in Nature and in ppenzell:
History; &c. Editor of the Alpine Journal, 1880-1889; &c. Arnaud, Henri,
W. A. P. WALTER ALIsoN PHILLIPs, M.A.
Principal Assistant Editor of the 11th edition of the Encyclopaedia Britannica. Archbishop;
Formerly Exhibitioner of Merton College, Oxford, and Senior Scholar of St John's Archdeacon.
College. . Author of Modern Europe; &c.
W. Bo. WILHELM Bousset, D.THEol.
Professor of New Testament Exegesis in the University of Göttingen. Author of Antichrist.
Das Wesen der Religion; The Antichrist Legend; &c.
W. Cr. WALTER CRANE. Arts and Crafts;
See the biographical article: CRANE, WALTER. Art Teaching.
W. E. Co. Ric: £ W: # £, D.D., £ of GIBRALTAR. L
ormer rolessor o clesiastical History, King's College, London. Lecturer,
St John's and Selwyn Colleges, Cambridge. Author of # Beginnings of English | Apostolical Constitutions.
Christianity.
W. E. E. M* # £ ld A -
aptain and Brevet Major, Royal Field Artillery. Inspector, Inspection Staff, Wool-
wich Arsenal. Lecturer on Armour and Explosives at the Royal Naval War Armour Plates.
College, Greenwich, 1904-1909.
W. F. C. WILLIAM FEILDEN CRAIES, M.A.
Barrister-at-law, Inner Temple. Lecturer on Criminal Law, King's College, London. Appeal
#" of Archbold's Criminal Pleading (23rd edition). Author of Craies on Statute p
to.
W. F. Sh. WILLIAM FLEET wood SHEPPARD, M.A., D.Sc.
Senior Examiner under the Board of Education. Senior Wrangler, 1884. Formerly 3 Arithmetic.
Fellow of Trinity College, Cambridge.
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 Angel, Atonement.
College, Sheffield. Author of Religion of the Post-Exilic Prophets; &c.
W. H. D1. WILLIAM HENRY DINEs, F.R.S. { Anemometer.
W. J. F. WILLIAM JUSTICE FoRD, M.A. (d. #!.
£y Scholar of St John's College, Cambridge. Head Master of Leamington { Archery.
oilege.
W. Ma. SIR WILLIAM MARKBY, K.C.I.E., D.C.L.
See the biographical article: Markey, SiR W. {Auth. John.
W. M. R. WILLIAM MICHAEL RossETTI.
See the biographical article: RossETT1, DANTE GABRiel. {Angelico, Fra.
W. P. R. HoN. WILLIAM PEMBER REEVEs.
Director, London School of Economics. Agent-General and High Commissioner: Atkinson, Sir Henry Albert.
for New Zealand, 1896-1909. Author of A History of New Zealana.
W. R. L. W. R. LETHABY, F.S.A. -
Principal of the Central School of Arts and Crafts under the London c. [*: £"
Council. Author of Architecture, Mysticism and Myth; &c. and Gothic in France.
W. W. WILLIAM WALLACE, M.A. - -
See the biographical article: WALLACE, WILLIAM (d. 1897). { Arabian Philosophy (in part).
W. W. F." WillIAM WARDE Fowler, M.A. -
Fellow of Lincoln College, Oxford. Sub-Rector, 1881–1904. Gifford Lecturer, J Anna Perenna;
Edinburgh University, 1908. Author of The City-State of the Greeks and Romans; Argel.
The Roman Festivals of the Republican Period; &c.
tioch, Synods of;
W. W. R." WILLIAM WALKEE Rockwell, Lic: THEo: . - - / {:£ of; 0
Assistant Professor of Church History, Union Theological Seminary, New York. Augsburg, Confession ol,
PRINCIPAL UNSIGNED ARTICLES
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tion in Labour Disputes.

ENCYCLOPAEDIA

BRITANNICA

ELEVENTH EDITION

VOLUME II

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 2ooo 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,ooo 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 Althis, 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

ANDÚjAR (the anc. Sliturgi), a town of southern Spain, in the province of Jaén; on the right bank of the river Guadalquivir and the Madrid-Cordova railway. Pop. (1900) 16,302. Andójar 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.

ANECD0TE (from äv-, privative, and #xölöwu, 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 Alsacc; 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. &veuos, wind, and uérpov, 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 publisations have often been in error by nearly 50%.

The other forms of velocity anemometermay 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 along 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 becn 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

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