Part 6

ACIERAGE ([=a]'s[=e]-[.e]r-[=a]j), (Fr. _acier_, steel), a process by which an engraved copper-plate or an electrotype from an engraved plate of steel or copper has a film of iron deposited over its surface by electricity in order to protect the engraving from wear in printing. By this means an electrotype of a fine engraving, which, if printed directly from the copper, would not yield 500 good impressions, can be made to yield 3000 or more; and when the film of iron becomes so worn as to reveal any part of the copper, it may be removed and a fresh coating deposited so that 20,000 good impressions may be got.

ACIPENSER (as-i-pen's[.e]r), the genus of cartilaginous ganoid fishes to which the sturgeon belongs.

ACI REALE ([:a]'ch[=e] r[=a]-[:a]'l[=a]), a seaport of Sicily, north-east of Catania, a well-built town, with a trade in corn, wine, fruit, &c. Pop. 35,587.

A'CIS, according to Ovid, a beautiful shepherd of Sicily, loved by Galatea, and crushed to death by his rival the Cyclops Polyphemus. His blood, flowing from beneath the rock which crushed him, was changed into a river bearing his name, and renowned for the coldness of its water. It has been identified as the Fiume di Jaci.

ACLIN'IC LINE (Gr. priv. _a, klin[=o]_, to incline), the magnetic equator, an irregular curve in the neighbourhood of the terrestrial equator, where the magnetic needle balances itself horizontally, having no dip. See _Magnetism_.

ACNE (ak'n[=e]), a skin disease, consisting of small hard pimples, usually on the face, caused by congestion of the follicles of the skin.

[Illustration: Acolyte]

ACOLYTES (ak'o-l[=i]ts), in the ancient Latin and Greek Churches, persons of ecclesiastical rank next in order below the subdeacons, whose office it was to attend the officiating priest. The name is still retained in the Roman Church. Cf. Duchesne, _Christian Worship, its Origin and Evolution_.

ACONCAGUA ([.a]-kon-k[:a]'gw[.a]), a province, a river, and a mountain of Chile. The peak of Aconcagua, whose summit is just within the Argentine Republic, rises to the height of 23,080 feet, and is probably the highest mountain of the western hemisphere. Area of province, 5406 sq. miles. Pop. (1919), 132,165.

AC'ONITE (_Acon[=i]tum_), a genus of hardy herbaceous plants, nat. ord. Ranunculaceae, represented by the well-known wolf's-bane or monk's-hood, and remarkable for their poisonous properties and medicinal qualities, being used internally as well as externally in rheumatism, gout, neuralgia, &c.

ACON'ITINE, an alkaloid extracted from monk's-hood and some other species of aconite; used medicinally, though a virulent poison.

ACONQUIJA ([.a]-kon-k[=e]'_h_[.a]), a range of mountains in the Argentine Republic; the name also of a single peak, 17,000 feet high.

A'CORN, the fruit of the different kinds of oak. The acorn-cups of one species are brought from the Levant under the name of _valonia_, and used in tanning.

ACORN-SHELL. See _Balanus_.

AC'ORUS, a genus of plants, including the sweet-flag. See _Sweet-flag_ and _Calamus_.

ACOS'TA, Gabriel, afterwards Uriel, a Portuguese of Jewish descent, born at Oporto in 1590, died by his own hand 1640. Brought up a Christian, he afterwards embraced Judaism. Having gone to Amsterdam, where he attacked the practices of the Jews, and denied the divine mission of Moses, he suffered much persecution at the hands of the Jews. He left an autobiography, published in 1687, under the title _Exemplar Humanae Vitae_. He is the hero of a novel, _Die Sadducaeer von Amsterdam_, and of a tragedy, _Uriel Acosta_, both by Gutzkow.

ACOTYLE'DONS, plants not furnished with cotyledons or seed-lobes. They include ferns, mosses, seaweeds, &c., and are also called flowerless plants or cryptogams.

ACOUSIMETER, or ACOUMETER (Gr. _akouein_, to hear, and _metron_, measure), an instrument used to determine the acuteness of hearing. It consists of a small bar which gives a uniform sound when struck by a hammer.

ACOUSTICS (a-kou'stiks), the science of sound. It deals with the production of sound, its propagation and velocity in various media; the reflection, refraction, and interference of sound waves; the properties of musical notes; and the general phenomena of such vibrations of elastic bodies as affect the organ of hearing.

In order that a sound may be heard, it is necessary that an uninterrupted series of particles of elastic matter should extend from the sounding body to our ear. Sound is propagated by a longitudinal wave-motion in the medium (gaseous, liquid, or solid), that is, the particles oscillate along the line in which the wave is travelling, giving rise to regular series of condensations and rarefactions.

The velocity of sound varies directly as the square root of the elasticity, and inversely as the square root of the density, of the medium in which it is propagated. The velocity of sound in air at 0deg C. is 330.6 metres per second, or 1085 feet per second; in water 1.49 kilometres per second, or 0.926 mile per second; in copper 5.01 kilometres per second, or 3.12 miles per second.

The intensity of sound varies inversely as the square of the distance from the sounding body. Recently sound-ranging instruments have been produced by means of which the position of a gun can be determined.

A note produced by a musical instrument consists of a _fundamental_ of a certain frequency, together with a number of _overtones_ of various higher frequencies and much smaller amplitude. The _timbre_ of a note depends on the overtones present, the _loudness_ depends on the amplitude of the vibrations, and the _pitch_ depends on the frequency. The musical scale consists of eight notes, C D E F G A B C, whose frequencies are in the proportion of the numbers 24, 27, 30, 32, 36, 40, 45 and 48. The interval between two notes is the ratio of the frequency of the higher note to the frequency of the lower note. In order that the intervals may be the same in all keys, a tempered scale is used in music. (See Table, p. 25.)

BIBLIOGRAPHY: Lord Rayleigh, _Theory of Sound_; H. Smith, _The Making of Sound in the Organ and Orchestra_; J. W. Capstick, _Sound_ (Cambridge Natural Science Manuals); E. H. Barton, _Text-book of Sound_.

ACQUI ([.a]k'w[=e]), a town of Northern Italy, 18 miles S.S.W. of Alessandria, a bishop's see. It has warm sulphurous baths, which were known to the Romans, and which still attract a great many visitors. Pop. 16,500.

ACRE, a standard British measure of land, also used in the colonies and the United States. The imperial statute acre consists of 4840 sq. yards, divided into 4 roods. The old Scotch acre contains 6146.8 sq. yards, the old Irish acre 7840 sq. yards.

ACRE ([=a]'k[.e]r) (ancient ACCHO and PTOLEMAIS), a seaport of Syria, in Northern Palestine, on the Bay of Acre, early a place of great strength and importance. Taken from the Saracens under Saladin in 1191 by Richard I of England and Philip of France; bravely defended by the Turks, assisted by Sir Sidney Smith, in 1799 against Napoleon; in 1832, taken by Ibrahim Pasha; in 1840, bombarded by a British, Austrian, and Turkish fleet, and restored to the Sultan of Turkey. The town was occupied by British troops under General Allenby in September, 1918. Pop. 10,000.

* * * * *

MUSICAL INTERVALS.--See _Acoustics_

Intervals in Intervals in Perfect Diatonic Diatonic Scale. Tempered Scale-- Scale. Perfect on System of Mean tone. Diatonic Scale Equal (2^{1/6} = 1.123). Temperament. Semitone. (2^{1/12}= 1.059). --------------------------------------------------------------------- C 1 1.000 9/8 major tone tone. D 9/8 = 1.125 2-2/12 = 1.123 10/9 minor tone tone. E 5/4 = 1.250 2-4/12 = 1.260 16/15 limma semitone. F 4/3 = 1.333 2-5/12 = 1.335 9/8 major tone tone. G 3/2 = 1.500 2-7/12 = 1.498 10/9 minor tone tone. A 5/3 = 1.667 2-9/12 = 1.682 9/8 minor tone tone. B 15/8 = 1.875 2-11/12 = 1.888 16/15 limma semitone. C' 2 2.000

Major tone ratio = 9/8 = 1.125 Limma tone ratio = 16/15 = 1.067 Minor " " = 10/9 = 1.111 Semitone " = 2^{1/12} = 1.059 Mean " " = 2^{2/12} = 1.123

NOTES OF PERFECT DIATONIC SCALE (WITH THEIR FREQUENCIES)

C,, 64. Ut_1 C, 128. Ut_2 C 256. Ut_3 C' 512. Ut_4 D,, 72 D, 144 D 288 D' 576 E,, 80 E, 160 E 320 E' 640 F,, 85.3 F, 170.7 F 341.3 F' 682.7 G,, 96 G, 192 G 384 G' 768 A,, 106.6 A, 213.3 A 426.7 A' 853.2 B,, 120 B, 240 B 480 B' 960 C'' 1024. Ut_5

PERFECT DIATONIC SCALES (TRANSITION TO KEY OF DOMINANT)

_Example_--Key of C to Key of G

C D E F G A B C' D' E' F' G' 1 9/8 5/4 4/3 3/2 5/3 15/8 2 9/4 5/2 8/3 3

G A` B C' D' E' F'# G' 1 9/8 5/4 4/3 3/2 5/3 15/8 2

A = 10/9 G. F' = 16/9 G. A`= 9/8 G. F'# = 15/8 G. A`= 81/80 A. = 15/8 X 9/16 F'. = (1 + 1/18{2/7}) F'.

* * * * *

ACRI ([=a]'kr[=e]), a town of S. Italy, province of Cosenza. Pop. 4000.

AC'RITA (Gr. _akritos_, undistinguishable, doubtful), a name sometimes given to the animals otherwise called Protozoa.

ACROCEPH'ALI, tribes of men distinguished by pyramidal or high skulls.

ACROCERAU'NIA (thunder-smitten peaks) (now CAPE GLOSSA or LINGUETTA), a promontory of Western Greece, in Epirus, running into the Adriatic.

ACROCORIN'THUS, a steep rock in Greece, nearly 1900 feet high, overhanging ancient Corinth, and on which stood the acropolis or citadel, the sacred fountain of Pir[=e]n[=e] being also here. This natural fortress has proved itself of importance in the modern history of Greece.

AC'ROGENS (-jenz), lit. summit-growers, a term applied to the ferns, mosses, and lichens (cryptogams), as growing by extension upwards, in contradistinction to endogens and exogens.

AC'ROLITH, an early form of Greek statuary in which the head, hands, and feet only were of stone, the trunk of the figure being of wood draped or gilded.

ACROP'OLIS (Gr. _akros_, high, and _polis_, a city), the citadel or chief place of a Grecian city, usually on an eminence commanding the town. That of Athens contained some of the finest buildings in the world, such as the Parthenon, Erechth[=e]um, &c.

ACROS'TIC, a poem of which the first or last, or certain other, letters of the line, taken in order, form some name, motto, or sentence. A poem of which both first and last letters are thus arranged is called a double acrostic. In Hebrew poetry, the term is given to a poem of which the initial letters of the lines or stanzas were made to run over the letters of the alphabet in their order, as in _Psalm_ cxix.--Acrostics have been much used in complimentary verses, the initial letters giving the name of the person eulogized. They were very popular among French poets of the sixteenth and seventeenth centuries. In modern times Edgar Allen Poe has written quite remarkable acrostic verses.

ACT, in special senses: (1) In dramatic poetry, one of the principal divisions of a drama, in which a definite and coherent portion of the plot is represented; generally subdivided into smaller portions called _scenes_. The Greek dramas were not divided into acts. The dictum that a drama should consist of five acts was first formally laid down by Horace, and is generally adhered to by modern dramatists in tragedy. In comedy, especially since the time of Moliere, more freedom is allowed, and a division into two or three acts is common.--(2) Something formally done by a legislative or judicial body; a statute or law passed.--(3) In universities, a thesis maintained in public by a candidate for a degree. See _Act of God_, _of Parliament_, _of Settlement_.

ACTA DIUR'NA (Lat., proceedings of the day), a daily Roman newspaper which appeared under both the republic and the empire.

ACTAE'A. See _Baneberry_.

ACTAE'ON, in Greek mythology, a great hunter, turned into a stag by Art[)e]mis (Diana) for looking on her when she was bathing, and torn to pieces by his own dogs.

ACTA ERUDITO'RUM (Lat., acts of the learned), the first literary journal that appeared in Germany (1682-1782). It was started by Otto Mencke, after the model of the _Journal des Savants_. Among the contributors, the most distinguished was Leibnitz.

ACTA SANCTORUM (Lat., acts of the saints), a name applied to all collections of accounts of ancient martyrs and saints, both of the Greek and Roman Churches, more particularly to the valuable collection begun by John Bolland, a Jesuit of Antwerp, in 1643, and which, being continued by other divines of the same order (_Bollandists_), now extends to sixty volumes, the lives following each other in the order of the calendar.

## ACTIN'IA, the genus of animals to which the typical sea-anemones belong.

See _Sea-anemone_.

AC'TINISM, the property of those rays of light which produce chemical changes, as in photography, in contradistinction to the light rays and heat rays. The actinic property or force begins among the green rays, is strongest in the violet rays, and extends a long way beyond the visible spectrum.

## ACTINIUM, an element or elementary substance obtained in minute quantities

in connection with the study of radioactivity. It was discovered by Debierne in 1899. In 1902 Giesel discovered another substance which he called _emanium_, and which was considered to be identical with _actinium_. Marckwald, however, came to the conclusion that these two substances are not identical but closely related to each other. See _Radium_, _Chemistry_.

## ACTIN'OLITE, a mineral nearly allied to hornblende.

## ACTINOM'ETER, an instrument for measuring the intensity of the sun's

## actinic rays. See _Actinism_.

## ACTINOZO'A (lit. ray-animals), a class of animals belonging to the

sub-kingdom Coelenterata, and including sea-anemones, corals, &c., all having rayed tentacles round the mouth.

## ACTION, the mode of seeking redress at law for any wrong, injury, or

deprivation. Actions are divided into civil and criminal, the former again being divided into real, personal, and mixed.

AC'TIUM (now LA PUNTA), a promontory on the western coast of Northern Greece, not far from the entrance of the Ambracian Gulf (Gulf of Arta), memorable on account of the naval victory gained here by Octavianus (afterwards the Emperor Augustus) over Antony and Cleopatra, 2nd Sept., 31 B.C., in sight of their armies encamped on the opposite shores of the Ambracian Gulf. Soon after the beginning of the battle Cleopatra escaped with sixty Egyptian ships, and Antony basely followed her, and fled with her to Egypt. The deserted fleet was not overcome without making a brave resistance. Antony's land forces soon went over to the enemy, and the Roman world fell to Octavianus. In 1538 a victory was gained at Actium by the Turks over the Spanish and Venetian fleets.

ACT OF GOD, a legal term defined as "a direct, violent, sudden, and irresistible act of nature, which could not, by any reasonable cause, have been foreseen or resisted". No one can be legally called upon to make good loss so arising.

ACT OF PARLIAMENT, a law or statute proceeding from the Parliament of the United Kingdom passed in both houses, and having received the royal assent. Before it is passed it is a _Bill_ and not an Act. Acts are either public or private, the former affecting the whole community, the latter only special persons and private concerns. The whole body of public Acts constitutes the _statute law_. An Act of Parliament can only be altered or repealed by the authority of Parliament. Acts are usually cited in this way, "13 and 14 Vict. c. (or chap.) 21", which means the 21st Act in succession passed in year 13th-14th of the queen's reign (that is, 1850). Short titles, such as "the Merchant Shipping Act, 1854", are also used. Up to the time of Edward I Acts of Parliament were in Latin; then French was introduced, and for some time was exclusively employed. It was not till Henry VII's reign that all Acts were in English.

ACT OF SETTLEMENT, an Act passed by the English Parliament in 1700, by which the succession to the throne of the three kingdoms, in the event of King William and Princess (afterwards Queen) Anne dying without issue, was settled on the Princess Sophia, electress of Hanover, and the heirs of her body, being Protestants. The Princess Sophia was the youngest daughter of Elizabeth, Queen of Bohemia, daughter of James I. By this act George I, son of the Princess Sophia, succeeded to the crown on the death of Queen Anne.--Another Act of Settlement was that by which, under Cromwell's government, a new allotment was made of almost all landed property in Ireland, in 1652.

ACT OF TOLERATION, an Act of Parliament Passed in 1689, by which Protestant dissenters from the Church of England, on condition of their taking the oaths of supremacy and allegiance, and repudiating the doctrine of transubstantiation, were relieved from the restrictions under which they had formerly lain with regard to the exercise of their religion according to their own forms.

ACT OF UNIFORMITY, an English Act passed in 1662, enjoining upon all ministers to use the _Book of Common Prayer_ on pain of forfeiture of their livings. See _Nonconformity_.

[Illustration: Quilted Acton of the fifteenth century]

ACTON, a kind of padded or quilted vest or tunic formerly worn under a coat of mail to save the body from bruises, or used by itself as a defensive garment. Jackets of leather or other material plated with mail were also so called. _Gambeson_ was an equivalent term.

ACTON, a name of various places in England, one of them a western suburb of London, pop. (1921), 61,314. Since 1918 Acton gives its name to a parliamentary division of Middlesex, returning one member to Parliament.

ACTON, John Emerich Edward Dalberg, first Baron Acton, born 1834, died 1902, was son of Richard Acton (seventh baronet) and the daughter of the Duc de Dalberg, afterwards wife of Earl Granville, Mr. Gladstone's colleague. As a Roman Catholic he was educated at Oscott, and afterwards on the Continent, partly under Doellinger, and acquired a special taste for and profound knowledge of history. He conducted the _Home and Foreign Review_ from 1862 to 1864, and, in doing so, showed himself a strong opponent of ultramontane pretensions. He next edited the _North British Review_, which under him was rather overweighted with learning, and soon came to an end. In 1869 he was raised to the peerage. He strongly opposed the papal-infallibility movement, and took the side of Mr. Gladstone in his attacks on Vaticanism. In 1895 he accepted the professorship of modern history at Cambridge, delivered lectures, and planned and undertook the editorship of the great work on modern history, _The Cambridge Modern History_, comprising a series of contributions by various scholars, and issued by the university press. Except essays, letters, or articles for periodicals, he himself wrote little. Since his death have been published: _Lectures in Modern History_ (1906); _The History of Freedom and other Essays_ (1907); _Lectures on the French Revolution_ (1910). His library of 60,000 volumes he left to Mr. (now Lord) Morley, who handed it over to the University of Cambridge.

ACTOR, one who represents some part or character on the stage. Actresses were unknown to the Greeks and Romans in the earliest times, men or boys always performing the female parts. They appeared under the Roman empire, however. Charles II first encouraged the public appearance of actresses in England; in Shakespeare's time there were none. See _Drama_.--BIBLIOGRAPHY: C. F. Armstrong, _Century of Great Actors_; H. Simpson, _Century of Great Actresses_.

ACTS OF THE APOSTLES, fifth of the books of the New Testament, written in Greek and assigned to the author of the gospel of St. Luke. Its date is probably A.D. 63 or 64. It embraces a period of about thirty years, beginning immediately after the resurrection, and extending to the second year of the imprisonment of St. Paul in Rome. Very little information is given regarding any of the apostles, excepting St. Peter and St. Paul, and the accounts of them are far from being complete. It describes the gathering of the infant Church; the fulfilment of the promise of Christ to his apostles in the descent of the Holy Ghost; the choice of Matthias in the place of Judas, the betrayer; the testimony of the apostles to the resurrection of Jesus in their discourses; their preaching in Jerusalem and in Judea, and afterwards to the Gentiles; the conversion of Paul, his preaching in Asia Minor, Greece, and Italy, his miracles and labours.--BIBLIOGRAPHY: R. T. Knowling, _The Expositor's Greek Testament_; J. Moffatt, _The Historical New Testament_; J. M. Wilson, _Origin and Aim of the Acts of the Apostles_.

AC'TUARY, an accountant whose business is to make the necessary computations in regard to a basis for life assurance, annuities, reversions, &c.

ACU'LEUS, in botany, a prickle, or sharp-pointed process of the epidermis, as distinguished from a thorn or spine, which is of a woody nature.

ACUPRESS'URE, a means of arresting bleeding from a cut artery introduced by Sir James Simpson in 1859, and consisting in compressing the artery above the orifice, that is, on the side nearest the heart, with the middle of a needle (Lat. _acus_, a needle) introduced through the tissues.

ACUPUNC'TURE, a surgical operation, consisting in the insertion of needles into certain parts of the body for alleviating pain, or for the cure of different species of rheumatism, neuralgia, eye diseases, &c. It is easily performed, gives little pain, causes neither bleeding nor inflammation, and seems at times of surprising efficacy.

ADAGIO (It. [.a]-d[:a]'j[=o]), a musical term, expressing a slow time, slower than _andante_ and less so than _largo_, _lento_, and _grave_.

ADAL', a country in Africa, east of Abyssinia and north-westward of Tajurrah Bay, inhabited by a dark-brown race of the same name, a tribe of the Danakils, Mahommedans in religion; towns Aussa and Tajurrah. Part of the coast here is held by the French.

AD'ALBERT OF PRAGUE, called the apostle of the Prussians, son of a Bohemian nobleman named Slavnik, born about 939. His real name was Voitech, but he assumed the name of the Archbishop Adalbert, under whom he studied at Magdeburg. He was appointed Bishop of Prague in 983, laboured in vain among the heathenish Bohemians, resolved to convert the pagans of Prussia, but was murdered in the attempt (997). _Boga-Rodzica_, a Polish war-song, is said to have been composed by him.

ADA'LIA, a seaport on the south coast of Asia Minor. Pop. 28,000. The district of Adalia has a population of over 200,000.

ADAM ([.a]-d[.a][n.]), Adolphe Charles, a French composer, more especially of comic operas; born 1803, died 1856. Wrote _Le postillon de Longjumeau_, _Le Brasseur de Preston_ (Brewer of Preston), _La Rose de Peronne_, _Le roi d'Yvetot_, &c.

ADAM, Albrecht, a German painter of battles and animals, born 1786, died 1862. Three sons of his have also distinguished themselves as painters, especially Franz, born 1815, died 1886, among whose best pictures are several representing scenes of the Franco-Prussian war.

ADAM, Alexander, a Scottish classical scholar, born in 1741; became in 1768 rector of the High School of Edinburgh, and died there in 1809. Wrote _Principles of Latin and English Grammar_; _Roman Antiquities_, a useful school-book; _Summary of Geography and History_; _Classical Biography_, &c.

ADAM, Robert, an eminent Scottish architect, born in 1728, a son of William Adam, architect. He resided several years in Italy, visited Spalatro, in Dalmatia, and published a work on the ruined palace of Diocletian there. In conjunction with his brother James he was much employed by the English nobility and gentry in constructing modern and embellishing ancient mansions. Among their works are the Register House and the University Buildings, Edinburgh, and the Adelphi Buildings, London. Robert Adam died in 1792, and was buried in Westminster Abbey; his brother James died in 1794.