ACHAEAN LEAGUE, a confederation of the ancient towns of Achaea. Standing isolated on their narrow strips of plain, these towns were always exposed to the raids of pirates issuing from the recesses of the north coast of the Corinthian Gulf. It was no doubt as a protection against such dangers that the earliest league of twelve Achaean cities arose, though we are nowhere explicitly informed of its functions other than the common worship of Zeus Amarius at Aegium and an occasional arbitration between Greek belligerents. Its importance grew in the 4th century, when we find it fighting in the Theban wars (368-362 B.C.), against Philip (338) and Antipater (330). About 288 Antigonus Gonatas dissolved the league, which had furnished a useful base for pretenders against Cassander's regency; but by 280 four towns combined again, and before long the ten surviving cities of Achaea had renewed their federation. Antigonus' preoccupation during the Celtic invasions, Sparta's prostration after the Chremonidean campaigns, the wealth amassed by Achaean adventurers abroad and the subsidies of Egypt, the standing foe of Macedonia, all enhanced the league's importance. Most of all did it profit by the statesmanship of Aratus (q.v.), who initiated its expansive policy, until in 228 it comprised Arcadia, Argolis, Corinth and Aegina.

Aratus probably also organized the new federal constitution, the character of which, owing to the scanty and somewhat perplexing nature of our evidence, we can only approximately determine. The league embraced an indefinite number of city-states which maintained their internal independence practically undiminished, and through their several magistrates, assemblies and law-courts exercised all traditional powers of self-government. Only in matters of foreign politics and war was their competence restricted.

The central government, like that of the constituent cities, was of a democratic cast. The chief legislative powers resided in a popular assembly in which every member of the league over thirty years of age could speak and vote. This body met for three days in spring and autumn at Aegium to discuss the league's policy and elect the federal magistrates. Whatever the number of its attendant burgesses, each city counted but one on a division. Extraordinary assemblies could be convoked at any time or place on special emergencies. A council of 120 unpaid delegates, selected from the local councils, served partly as a committee for preparing the assembly's programme, partly as an administrative board which received embassies, arbitrated between contending cities and exercised penal jurisdiction over offenders against the constitution. But perhaps some of these duties concerned the dicastae and gerousia, whose functions are nowhere described. The chief magistracy was the strategia (tenable every second year), which combined with an unrestricted command in the field a large measure of civil authority. Besides being authorized to veto motions, the strategus (general) had practically the sole power of introducing measures before the assembly. The ten elective demiurgi, who presided over this body, formed a kind of cabinet, and pethaps acted as departmental chiefs. We also hear of an under-strategus, a secretary, a cavalry commander and an admiral. All these higher officers were unpaid. Philopoemen (q.v.) transferred the seat of assembly from town to town by rotation, and placed dependent communities on an equal footing with their former suzerains.

The league prescribed uniform laws, standards and coinage; it summoned contingents, imposed taxes and fined or coerced refractory members.

The first federal wars were directed against Macedonia; in 266-263 the league fought in the Chremonidean league, in 243-241 against Antigonus Gonatas and Aetolia, between 239 and 229 with Aetolia against Demetrius. A greater danger arose (227-223) from the attacks of Cleomenes III. (q.v.). Owing to Aratus's irresolute generalship, the indolence of the rich burghers and the inadequate provision for levying troops and paying mercenaries, the league lost several battles and much of its territory; but rather than compromise with the Spartan Gracchus the assembly negotiated with Antigonus Doson, who recovered the lost districts but retained Corinth for himself (223-221). Similarly the Achaeans could not check the incursions of Aetolian adventurers in 220-218, and when Philip V. came to the rescue he made them tributary and annexed much of the Peloponnese. Under Philopoemen the league with a reorganized army routed the Aetolians (210) and Spartans (207, 201). After their benevolent neutrality during the Macedonian war the Roman general, T. Quinctius Flamininus, restored all their lost possessions and sanctioned the incorporation of Sparta and Messene (191), thus bringing the entire Peloponnese under Achaean control. The league even sent troops to Pergamum against Antiochus (190). The annexation of Aetolia and Zacynthus was forbidden by Rome. Moreover, Sparta and Messene always remained unwilling members. After Philopoemen's death the aristocrats initiated a strongly philo-Roman policy, declared war against King Perseus and denounced all sympathizers with Macedonia. This agitation induced the Romans to deport 1000 prominent Achaeans, and, failing proof of treason against Rome, to detain them seventeen years. These hostages, when restored in 150, swelled the ranks of the proletariate opposition, whose leaders, to cover their maladministration at home, precipitated a war by attacking Sparta in defiance of Rome. The federal troops were routed in central Greece by Q. Caecilius Metellus Masedonicus, and again near Corinth by L. Mummius Achaicus (146). The Romans now dissolved the league (in effect, if not in name), and took measures to isolate the communities (see POLYBIUS). Augustus instituted an Achaean synod comprising the dependent cities of Peloponnese and central Greece; this body sat at Argos and acted as guardian of Hellenic sentiment.

The chief defect of the league lay in its lack of proper provision for securing efficient armies and regular payment of imposts, and for dealing with disaffected members. Moreover, owing to difficulties of travel, the assembly and magistracies were practically monopolized by the rich, who shaped the federal policy in their own interest. But their rule was mostly judicious, and when at last they lost control the ensuing mob-rule soon ruined the country. On the other hand, it is the glory of the Achaean league to have combined city autonomy with an organized central administration, and in this way to have postponed the entire destruction of Greek liberty for over a century.

CHIEF SOURCES.—Polybius (esp. bks. ii., iv., v., xxiii., xxviii.),who is followed by Livy (bks. xxxii.-xxxv., xxxviii., &c.); Pausanias vii. 9-24; Strabo viii. 384; F. Freeman, Federal Government, i. (ed. 1893, London), chs. v.-ix.; M. Dubois, Les lignes Etolienne et Acheenne (Paris, 1885); A. Holm, Greek History, iv.; G. Hertzberg, Geschichte Griechenlands unter den Romern, i. (Leipzig, 1866); L. Warren, Greek Federal Coinage (London, 1863); E. Hicks, Greek Historical Inscriptions (Oxford, 1892), 169, 187, 198, 201; W.. Dittenberger, Sylloge Inscriptionunn Graecarum (Leipzig, 1898—1901), 236, 282, 316; H. Francotte in Musee Belge (1906), pp. 4-20. See also art. ROME, History, ii. "The Republic,'' sect. B(b). (M. O. B. C.)

ACHAEANS ('Achaioi, Lat. Achivi), one of the four chief divisions of the ancient greek peoples, descended, according to legend, from Achaeus, son of Xuthus, son of Hellen. This Hesiodic genealogy connects the Achaeans closely with the Ionians, but historically they approach nearer to the Aeolians. Some even hold that Aeolus is only a form of Achaeus. In the Homeric poems (1000 B.C.) the Achaeans are the master race in Greece; they are represented both in Homer and in all later traditions as having come into Greece about three generations before the Trojan war (1184 B.C.), i.e. about 1300 B.C. They found the land occupied by a people known by the ancients as Pelasgians, who continued down to classical times the main element in the population even in the states under Achaean and later under Dorian rule. In some cases it formed a serf class, e.g. the Penestae in Thessaly, the Helots in Laconia and the Gymnesii at Argos, whilst it practically composed the whole population of Arcadia and Attica, which never came under either Achaean or Dorian rule. This people had dwelt in the Aegean from the Stone Age, and, though still in the Bronze Age at the Achaean conquest, had made great advances in the useful and ornamental arts. They were of short stature, with dark hair and eyes, and generally dolichocephalic. Their chief centres were at Cnossus (Crete), in Argolis, Laconia and Attica, in each being ruled by ancient lines of kings. In Argolis Proetus built Tiryns, but later, under Perseus, Mycenae took the lead until the Achaean conquest. All the ancient dynasties traced their descent from Poseidon, who at the time of the Achaean conquest was the chief male divinity of Greece and the islands. The Pelasgians probably spoke an Indo-European language adopted by their conquerors with slight modifications. (See further PELASGIANS for a discussion of other views.)

The Achaeans, on the other hand, were tall, fair-haired and grey-eyed, and their chiefs traced their descent from Zeus, Who with the Hyperborean Apollo was their chief male divinity. They first appear at Dodona, whence they crossed Pindus into Phthiotis. The leaders of the Achaean invasion were Pelops, who took possession of Elis, and Aeacus, who became master of Aegina and was said to have introduced there the worship of Zeus Panhellenius, whose cult was also set up at Olympia. They brought with them iron, which they used for their long swords and for their cutting implements; the costume of both sexes was distinct from that of the Pelasgians; they used round shields with a central boss instead of the 8-shaped or rectaogular shields of the latter; they fastened their garments with brooches, and burned their dead instead of burying them as did the Pelasgians. They introduced a special style of ornament ("geometric'') instead of that of the Bronze Age, characterized by spirals and marine animals and plants. The Achaeans, or Hellenes, as they were later termed, were on this hypothesis one of the fair-haired tribes of upper Europe known to the ancients as Keltoi (Celts), who from time to time have pressed down over the Alps into the southern lands, successively as Achaeans, Gauls, Goths and Franks, and after the conquest of the indigenous small dark race in no long time died out under climatic conditions fatal to their physique and morale. The culture of the Homeric Achaeans corresponds to a large extent with that of the early Iron Age of the upper Danube (Hallstatt) and to the early Iron Age of upper Italy (Villanova).

See W. Ridgeway, The Early Age of Greece (1901), for a detailed discussion of the evidence; articles by Ridgeway and J. L. Myres in the Classical Review, vol. xvi. 1902, pp. 68-93, 135. See also J. B. Bury's History of Greece (1902) and art. in Journal of Hellenic Studies, xv., 1895, pp. 217 foll.; G. G. A. Murray, Rise of the Greek Epic (1907), chap. ii.; Andrew Lang, Homer and his Age (1906); G. Busolt, Griech. Gesch. ed. 2, vol. i. p. 190 (1893); D. B. Monro's ed. of the Iliad (1901), pp. 484-488. (W. RI.)

ACHAEMENES (HAKHAMANI), the eponymous ancestor of the royal house of Persia, the Achaemenidae, "a clan fretre of the Pasargadae'' (Herod. i. 125), the leading Persian tribe. According to Darius in the Behistun inscription and Herod. iii. 75, vii. 11, he was the father of Teispes, the great-grandfather of Cyrus. Cyrus himself, in his proclamation to the Babylonians after the conquest of Babylon, does not mention his name. Whether he really was a historical personage, or merely the mythical ancestor of the family cannot be decided. According to Aelian (Hist. anim. xii. 21), he was bred by an eagle. We learn from Cyrus's proclamation that Teispes and his successors had become kings of Anshan, i.e. a part of Elam (Susiana), Where they ruled as vassals of the Median kings, until Cyrus the Great in 550 B.C. founded the Persian empire. After the death of Cambyses, the younger line of the Achaemenidae came to the throne with Darius, the son of Hystaspes, who was, like Cyrus, the great-grandson of Teispes. Cyrus, Darius and all the later kings of Persia call themselves Achaemenides (Hakhamanishiya). With Darius III. Codomannus the dynasty became extinct and the Persian empire came to an end (330). The adjective Achaemenius is used by the Latin poets as the equivalent of "Persian'' (Horace, Odes, ii. 12, 21). See PERSIA.

The name Achaemenes is borne by a son of Darius I., brother of Xerxes. After the first rebellion of Egypt, he became satrap of Egypt (484 B.C.); he commanded the Persian fleet at Salamis, and was (460 B.C.) defeated and slain by Inarus, the leader of the second rebellion of Egypt.

ACHARD, FRANZ CARL (1753—1821), Prussian chemist, was born at Berlin on the 28th of April 1753, and died at Kunern, in Silesia, on the 20th of April 1821. He was a pioneer in turning to practical account A. S. Marggraf's discovery of the presence of sugar in beetroot, and by the end of the 18th century he was producing considerable quantities of beet-sugar, though by a very imperfect process, at Kunern, on an estate which was granted him about 1800 by the king of Prussia. There too he carried on a school of instruction in sugar-manufacture, which had an international reputation. For a time he was director of the physics class of the Berlin Academy of Sciences, and he published several volumes of chemical and physical researches, discovering among other things a method of working platinum.

ACHARIUS, ERIK (1757-1819), Swedish botanist, was born On the 10th of October 1757, and in 1773 entered Upsala University, where he was a pupil of Linnaeus. He graduated M.D. at Lund in 1782, and in 1801 was appointed professor of botany at Wadstena Academy. He devoted himself to the study of lichens, and all his publications were connected with that class of plants, his Lichenographia Universalis (Gottingen, 1804) being the most important. He died at Wadstena on the 13th of August 1819.

ACHATES, the companion of Aeneas in Virgil's Aeneid. The expression "fidus Achates'' has become proverbial for a loyal and devoted companion.

ACHELOUS (mod. Aspropotamo, "white river''), the largest river in Greece (130 m.). It rises in Mt. Pindus, and, dividing Aetolla from Acarnania, falls into the Ionian Sea. In the lower part of its course the river winds through fertile, marshy plains. Its water is charged with fine mud, which is deposited along its banks and at its mouth, where a number of small islands (Echinades) have been formed. It was formerly called Thoas, from its impetuosity; and its upper portion was called by some Inachus, the name Acholous being restricted to the shorter eastern branch. Acholous is coupled with Ocean by Homer (Il. xxi. 193) as chief of rivers, and the name is given to several other rivers in Greece. The Dame appears in cult and in mythology as that of the typical river-god; a familiar legend is that of his contest with Heracles for Deianira.

ACHENBACH, ANDREAS (1815— ), German landscape painter, was born at Cassel in 1815. He began his art education in 1827 in Dusseldorf under W. Schadow and at the academy. In his early work he followed the pseudo-idealism of the German romantic school, but on removing to Munich in 1835, the strooger influence of L. Gurlitt turned his talent into new channels, and he became the founder of the German realistic school. Although his landscapes evince too much of his aim at picture-making and lack personal temperament, he is a master of technique, and is historically important as a reformer. A number of his finest works are to be found at the Berlin National Gallery, the New Pinakothek in Munich, and the galleries at Dresden, Darmstadt, Cologne, Dusseldorf, Leipzig and Hamburg.

His brother, OSWALD ACHENBACH (1827—1905), was born at Dusseldorf and received his art education from Andreas. His landscapes generally dwell on the rich and glowing effects of colour which drew him to the Bay of Naples and the neighbourhood of Rome. He is represented at most of the important German galleries of modern art.

ACHENWALL, GOTTFRIED (1719-1772), German statisticiao, was born at Elbing, in East Prussia, in October 1719. He studied at Jena, Halle and Leipzig, and took a degree at the last-named university. He removed to Marburg in 1746, where for two years he read lectures on history and on the law of nature and of nations. Here, too, he commenced those inquiries in statistics by which his name became known. In 1748 he was given a professorship at Gottingen, where he resided till his death in 1772. His chief works were connected with statistics. The Staatsverfassung der heutigen vornehmsten europaischen Reiche appeared first in 1749, and revised editions were published in 1762 and 1768.

ACHERON, in Greek mythology, the son of Gaea or Demeter. As a punishment for supplying the Titans with water in their contest with Zeus, he was turned into a river of Hades, over which departed souls were ferried by Charon. The name (meaning the river of "woe'') was eventually used to designate the whole of the lower world (Stobaeus, Ecl. Phys. i. 41, sec. sec. 50, 54).

ACHIACHARUS, a name occurring in the book of Tobit (i. 21 f.) as that of a nephew of Tobit and an official at the court of Esarhaddon at Nineveh. There are references in Rumanian, Slavonic, Armenian, Arabic and Syriac literature to a legend, of which the hero is Ahikar (for Armenian, Arabic and Syriac, see The Story of Ahikar, F. C. Conybeare, Rondel Harris and Agnes Lewis, Camb. 1898), and it was pointed out by George Hoffmann in 1880 that this Ahikar and the Achiacharus of Tobit are identical. It has been contended that there are traces of the legend even in the New Testament, and there is a striking similarity between it and the Life of Aesop by Maximus Planudes (ch. xxiii.-xxxii.). An eastern sage Achaicarus is mentioned by Strabo. It would seem, therefore, that the legend was undoubtedly oriental in origin, though the relationship of the various versions can scarcely be recovered.

See the Jewish Encyclopaedia and the Encyclopaedia Biblica; also M. R. James in The Guardian, Feb. 2, 1898, p. 163 f.

ACHILL ("Eagle''), the largest island off Ireland, separated from the Curraun peninsula of the west coast by the narrow Achill Sound. Pop. (1901) 4929. It is included in the county Mayo, in the western parliamentary division. Its shape is triangular, and its extent is 15 m. from E. to W. and 12 from N. to S. The area is 57 sq. m. The island is mountainous, the highest points being Slieve Croaghaun (2192 ft.) in the west, and Shevemore (2204 ft.) in the north; the extreme western point is the bold and rugged promontory of Achill Head, and the northwestern and south-western coasts consist of ranges of magnificent cliffs, reaching a height of 800 ft. in the cliffs of Minaun, near the village of Keel on the south. The seaward slope of Croaghaun is abrupt and in parts precipitous, and its jagged flanks, together with the serrated ridge of the Head and the view over the broken coast-line and islands of the counties Mayo and Galway, attract many visitors to the island during summer. Desolate bogs, incapable of cultivation, alternate with the mountains; and the inhabitants earn a scanty subsistence by fishing and tillage, or by seeking employment in England and Scotland during the harvesting. The Congested Districts Board, however, have made efforts to improve the Condition of the people, and a branch of the Midland Great Western railway to Achill Sound, together with a swivel bridge across the sound, improved communications and make for prosperity. Dugort, the principal village, contains several hotels. Here is a Protestant colony. known as "the Settlement'' and founded in 1834. There are antiquarian remains (cromlechs, stone circles and the like) at Slievemore and elsewhere.

ACHILLES (Gr. 'Achilleus), one of the most famous of the hegendary heroes of ancient Greece and the central figure of Homer's Iliad. He was said to have been the son of Peleus, king of the Myrmidones of Phthia in Thessaly, by Thetis, one of the Nereids. His grandfather Aeacus was, according to the legend, the son of Zeus himself. The story of the childhood of Achilles in Homer differs from that given by later writers. According to Homer, he was brought up by his mother at Phthia with his cousin and intimate friend Patroclus, and learned the arts of war and eloquence from Phoenix, while the Centaur Chiron taught him music and medicine. When summoned to the war against Troy, he set sail at once with his Myrmidones in fifty ships.

Post-Homeric sources add to the legend certain picturesque details which bear all the evidence of their primitive origin, and which in some cases belong to the common stock of Indo-Germanic myths. According to one of these stories Thetis used to lay the infant Achilles every night under live coals, anointing him by day with ambrosia, in order to make him immortal. Peleus, having surprised her in the act, in alarm snatched the boy from the flames; whereupon Thetis fled back to the sea in anger (Apollodorus iii. 13; Apollonius Rhodius iv. 869). According to another story Thetis dipped the child in the waters of the river Styx, by which his whole body became invulnerable, except that part of his heel by which she held him; whence the proverbial "heel of Achilles'' (Statius, Achilleis, i. 269). With this may be compared the similar story told of the northern hero Sigurd. The boy was afterwards entrusted to the care of Chiron, who, to give him the strength necessary for war, fed him with the entrails of lions and the marrow of bears and wild boars. To prevent his going to the siege of Troy, Thetis disguised him in female apparel, and hid him among the maidens at the court of King Lycomedes in Scyros; but Odysseus, coming to the island in the disguise of a pedlar, spread his wares, including a spear and shield, before the king's daughters, among whom was Achilles. Then he caused an alarm to be sounded; whereupon the girls fled, but Achilles seized the arms, and so revealed himself, and was easily persuaded to follow the Greeks (Hyginus, Fab. 96; Statius, Ach. i.; Apollodorus, l.c.). This story may be compared with the Celtic legend of the boyhood of Peredur or Perceval.

During the first nine years of the war as described in the Iliad, Achilles ravaged the country round Troy, and took twelve cities. In the tenth year occurred the quarrel with Agamemnon. In order to appease the wrath of Apollo, who had visited the camp with a pestilence, Agamemnon had restored Chryseis, his prize of war, to her father, a priest of the god, but as a compensation deprived Achilles, who had openly demanded this restoration, of his favourite slave Briseis. Achilles withdrew in wrath to his tent, where he consoled himself with music and singing, and refused to take any further part in the war. During his absence the Greeks were hard pressed, and at last he so far relaxed his anger as to allow his friend Patroclus to personate him, lending him his chariot and armour. The slaying of Patroclus by the Trojan hero Hector roused Achilles from his indifference; eager to avenge his beloved comrade, he sallied forth, equipped with new armour fashioned by Hephaestus, slew Hector, and, after dragging his body round the walls of Troy, restored it to the aged King Priam at his earnest entreaty. The Iliad concludes with the funeral rites of Hector. It makes no mention of the death of Achilles, but hints at its taking place "before the Scaean gates.'' In the Odyssey (xxiv. 36. 72) his ashes are said to have been buried in a golden urn, together with those of Patroclus, at a place on the Hellespont, where a tomb was erected to his memory; his soul dwells in the lower world, where it is seen by Odysseus. The contest between Ajax and Odysseus for his arms is also mentioned. The Aethiopis of Arctinus of Miletus took up the story of the Iliad. It told how Achilles, having slain the Amazon Penthesileia and Memnon, king of the Aethiopians, who had come to the assistance of the Trojans, was himself slain by Paris (Alexander), whose arrow was guided by Apollo to his vulnerable heel (Virgil, Aen. vi. 57; Ovid, Met. xii. 600). Again, it is said that Achilles, enamoured of Polyxena, the daughter of Priam, offered to join the Trojans on condition that he received her hand in marriage. This was agreed to; Achilles went unarmed to the temple of Apollo Thymbraeus, and was slain by Paris (Dietys iv. 11). According to some, he was slain by Apollo himself (Quint. Smyrn. iii. 61; Horace, Odes, iv. 6, 3). Hyginus (Fab. 107) makes Apollo assume the form of Paris.

Later stories say that Thetis snatched his body from the pyre and conveyed it to the island of Leuke, at the mouth of the Danube, where he ruled with Iphigeneia as his wife; or that he was carried to the Elysian fields, where his wife was Medea or Helen. He was worshipped in many places: at Leuke, where he was honoured with offerings and games; in Sparta, Elis, and especially Sigeum on the Hellespont, where his famous tumulus was erected.

Achilles is a typical Greek hero; handsome, brave, celebrated for his fleetness of foot, prone to excess of wrath and grief, at the same time he is compassionate, hospitable, full of affection for his mother and respect for the gods. In works of art he is represented, like Ares, as a young man of splendid physical proportions, with bristling hair like a horse's mane and a slender neck. Although the figure of the hero frequently occurs in groups—-such as the work of Scopas showing his removal to the island of Leuke by Poseidon and Thetis, escorted by Neroids and Tritons, and the combat over his dead body in the Aeginetan sculptures—no isolated statue or bust can with certainty be identified with him; the statue in the Louvre (from the Villa Borghese), which was thought to have the best claim, is generally taken for Ares or possibly Alexander. There are many vase and wall paintings and bas-reliefs illustrative of incidents in his life. Various etymologies of the name have been suggested: "without a lip'' (a', cheilos), Achilles being regarded as a river-god, a stream which overflows its banks, or, referring to the story that, when Thetis laid him in the fire, one of his lips, which he had licked, was consumed (Tzetzes on Lycophron, 178); "restrainer of the people,' (eche-laos); "healer of sorrow'' (ache-loios); "the obscure'' (connected with achlus, "mist''); "snakeborn'' (echis), the snake being one of the chief forms taken by Thetis. The most generally received view makes him a god of light, especially of the sun or of the lightning.

See E. H. Meyer, Indogermanische Mythen, ii., Achilleis, 1887; F. G. Welcker, Der epische Cyclus, 1865—1882; articles in Pauly-Wissowa, Rcal-Encyclopadie der classischen Altertumswissenschait, Daremberg and Saglio's Dictionnaire des Antiquites and Roscher's Lexikon der Mythologie; see also T. W. Allen in Classical Review, May 1906; A. E. Crawley, J. G. Frazer, A. Lang, Ibid., June, July 1893, on Achilles in Scyros. In the article GREEK ART, fig. 12 represents the conflict over the dead body of Achilles.

ACHILLES TATIUS, of Alexandria, Greek rhetorician, author of the erotic romance, the Adventures of Leucippe and Cleitophon, flourished about A.D. 450, perhaps later. Suidas, who alone calls him Statius, says that he became a Christian and eventually a bishop—like Hellodorus, whom he imitated—but there is no evidence of this. Photius, while severely criticizing his lapses into indecency, highly praises the conciseness and clearness of his style, which, however, is artificial and laboured. Many of the incidents of the romance are highly improbable, and the characters, except the heroine, fail to enlist sympathy. The descriptive passages and digressions, although tedious and introduced without adequate reasons, are the best part of the work. The large number of existing MSS. attests its popularity. (Editio princeps, 1601; first important critical edition by (Jacobs, 1821; litter editions by Hirschig, 1856; Hercher, 1858. There are translations in many languages; in English by Anthony Hodges], 1638, and R. Smith, 1855. See also ROMANCE.)

Suidas also ascribes to this author an Etymology, a Miscellaneous History af Famous Men, and a treatise On the Sphere. Part of the last is extant under the title of An Introduction to the Phaenomena of Aratus. But if the writer is the prudentissimus Achilles referred to by Firmicus Maternus (about 336) in his Matheseos libri, iv. 10, 17 (ed. Krolf), he must have lived long before the author of Leucippe. The fragment was first published in 1567, then in the Uranologion of Petavius, with a Latin translation, 1630. Nothing definite is known as to the authorship of the other works, which are lost.

ACHILLINI, ALESSANDRO (1463-1512), Italian philosopher, born on the 29th of October 1463 at Bologna, was celebrated as a lecturer both in medicine and in philosophy at Bologna and Padua, and was styled the second Aristotle. His philosophical works were printed in one volume folio, at Venice, in 1508, and reprinted with considerable additions in 1545, 1551 and 1568. He was also distinguished as an anatomist (see ANATOMY), among his writhigs being Corporis humani Anatomia (Venice, 1516-1524), and Anatomicae Annotationes (Bologna, 1520). He died at Bologna on the 2nd of August 1512.

His brother, GIOVANNI FILOTEO ACHILLINI (1466—1533), was the author of Il Viridario and other writings, verse and prose, and his grand-nephew, CLAUDIO ACHILLINI (1574—1640), was a lawyer who achieved some notoriety as a versifier of the school of the Secentisti.

ACHIMENES (perhaps from the Gr. achaimienis, an Indian plant used in magic), a genus of plants, natural order Gesneraceae (to which belong also Gloxinia and Streptocarpus), natives of tropical America, and well known in cultivation as stove or warm greenhouse plants. They are herbaceous perennials, generally with hairy serrated leaves and handsome flowers. The corolla is tubular with a spreading limb, and varies widely in colour, being white, yellow, orange, crimson, scarlet, blue or purple. A large number of hybrids exist in cultivation. The plants are grown in the stove till the flowering period, when they may be removed to the greenhouse. They are propagated by cuttings, or from the leaves, which are cut off and pricked in well-drained pots of sandy soil, or by the scales from the underground tubes, which are rubbed off and sown like seeds, or by the seeds, which are very small.

ACHIN (Dutch Atjeh), a Dutch government forming the northern extremity of the island of Sumatra, having an estimated area of 20,544 sq. m. The government is divided into three assistant-residencien—the east coast, the west coast and Great Achin. The physical geography (see SUMATRA) is imperfectly understood. Ranges of mountains, roughly parallel to the long axis of the island, and characteristic of the whole of it, appear to occupy the interior, and reach an extreme height of about 12,000 ft. in the south-west of the government. The coasts are low and the rivers insignificant, rising in the coast ranges and flowing through the coast states (the chief of which are Pedir, Gighen and Samalanga on the N.; Edi, Perlak and Langsar on the E.; Kluwah, Rigas and Melabuh on the W.). The chief ports are Olehleh, the port of Kotaraja or Achin (formerly Kraton, now the seat of the Dutch government), Segli on the N., Edi on the E., and Analabu or Melabuh on the W. Kotaraja lies near the northern extremity of the island, and consists of detached houses of timber and thatch, clustered ill enclosed groups called kampongs, and buried in a forest of fruit-trees. It is situated nearly 3 m. from the sea, in the valley of the Achin 1iver, which in its upper part, near Sehmun, is 3 m. broad, the river having a breadth of 99 ft. and a depth of 1 1/2 ft.; but in its lower course, north of its junction with the Krung Darn, the valley broadens to 12 1/2 m. The marshy soil is covered by rice-fields, and on higher ground by kampongs full of trees. The river at its mouth is 327 ft. broad and 20-33 ft. deep, but before it lies a sandbank covered at low water by a depth of only 4 ft. The Dutch garrison in Kotaraja occupies the old Achinese citadel. The town is connected by rail with Olehleh, and the line also extends up the valley. The construction of another railway has been undertaken along the east coast. The following industries are of some importance —gold-working, weapon-making, silk-weaving, the making of pottery, fishing and coasting trade. The annual value of the exports (chiefly pepper) is about L. 58,000; of the imports, from L. 165,000 to L. 250,000. The population of Achin in 1898 was estimated at 535,432, of whom 328 were Europeans, 3933 Chinese, 30 Arabs, and 372 other foreign Asiatics.

The Achinese, a people of Malayan stock but darker, somewhat taller and not so pleasant-featured as the true Malays, regard themselves as distinct from the other Sumatrans. Their nobles claim Arab descent. They were at one time Hinduized, as is evident from their traditions, the many Sanskrit words in their language, and their general appearance, which suggests Hindu as well as Arab blood. They are Mahommedans, and although Arab influence has declined, their nobles still wear the Moslem flowing robe and turban (though the women go unveiled), and they use Arabic script. The chief characteristic is their love of fighting; every man is a soldier and every village has its army. They are industrious and skilful agriculturists, metal-workers and weavers. They build excellent ships. Their chief amusements are gambling and opium-smoking. Their social organization is communal. They live in kampongs, which combine to form mukims, districts or hundreds (to use the nearest English term), which again combine to form sagis, of which there are three. Achin literature, unlike the language, is entirely Malay; it includes poetry, a good deal of theology and several chronicles. Northern Sumatra was visited by several European travellers in the middle ages, such as Marco Polo, Friar Odorico and Nicolo Conti. Some of these as well as Asiatic writers mention Lambri, a state which must have nearly occupied the position of Achin. But the first voyager to visit Achin, by that name, was Alvaro Tellez, a captain of Tristan d'Acunha's fleet, in 1506. It was then a mere dependency of the adjoining state of Pedir; and the latter, with Pasei, formed the only states on the coast whose chiefs claimed the title of sultan. Yet before twenty years had passed Achin had not only gained independence, but had swallowed up all other states of northern Sumatra. It attained its climax of power in the time of Sultan Iskandar Muda (1607—1636), under whom the subject coast extended from Aru opposite Malacca round by the north to Benkulen on the west coast, a sea-board of not less than 1100 miles; and besides this, the king's supremacy was owned by the large island of Nias, and by the continental Malay states of Johor, Pahang, Kedah and Perak.

The chief attraction of Achin to traders in the 17th century must have been gold. No place in the East, unless Japan, was so abundantly supplied with gold. The great repute of Achin as a place of trade is shown by the fact that to this port the first Dutch (1599) and first English (1602) commercial ventures to the Indies were directed. Sir James Lancaster, the English commodore, carried letters from Queen Elizabeth to the king of Achin, and was well received by the prince then reigning, Alauddin Shah. Another exchange of letters took place between King James I. and Iskandar Muda in 1613. But native caprice and jealousy of the growing force of the European nations in these seas, and the rivalries between those nations themselves, were destructive of sound trade; and the English factory, though several times set up, was never long maintained. The French made one great effort (1621) to establish relations with Achin, but nothing came of it. Still the foreign trade of Achin, though subject to interruptions, was important. William Dampier (c. 1688) and others speak of the number of foreign merchants settled there—English, Dutch, Danes, Portuguese, Chinese, &c. Dampier says the anchorage was rarely without ten or fifteen sail of different nations, bringing vast quantities of rice, as well as silks, chintzes, muslins and opium. Besides the Chinese merchants settled at Achin, others used to come annually with the junks, ten or twelve in number, which arrived in June. A regular fair was then established, which lasted two months, and was known as the China camp, a great resort of foreigners.

Hostilities with the Portuguese began from the time of the first independent king of Achin; and they had little remission till the power of Portugal fell with the loss of Malacca (1641). Not less than ten times before that event were armaments despatched from Achin to reduce Malacca, and more than once its garrison was hard pressed. One of these armadas, equipped by Iskandar Muda in 1615, gives an idea of the king's resources. It consisted of 500 sail, of which 250 were galleys, and among these a hundred were greater than any then used in Europe. Sixty thousand men were embarked.

On the death of Iskandar's successor in 1641, the widow was placed on the throne; and as a female reign favoured the oligarchical tendencies of the Malay chiefs, three more queens were allowed to reign successively. In 1699 the Arab or fanatical party suppressed female government, and put a chief of Arab blood on the throne. The remaining history of Achin was one of rapid decay.

After the restoration of Java to the Netherlands in 1816, a good deal of weight was attached by the neighbouring British colonies to the maintenance of influence in Achin; and in 1819 a treaty of friendship was concluded with the Calcutta government which excluded other European nationalities from fixed residence in Achin. When the British government, in 1824, made a treaty with the Netherlands, surrendering the remaining British settlements in Sumatra in exchange for certain possessions on the continent of Asia, no reference was made in the articles to the Indian treaty of 1819; but an understanding was exchanged that it should be modified, while no proceedings hostile to Achin should be attempted by the Dutch.

This reservation was formally abandoned by the British government in a convention signed at the Hague on the 2nd of November 1871; and in March 1873 the government of Batavia declared war upon Achin. Doubtless there was provocation, for the sultan of Achin had not kept to the understanding that he was to guarantee immunity from piracy to foreign traders; but the necessity for war was greatly doubted, even in Holland. A Dutch force landed at Achin in April 1873, and attacked the palace. It was defeated with considerable loss, including that of the general (Kohler).The approach of the south-west monsoon precluded the immediate renewal of the attempt; but hostilities were resumed, and Achin fell in January 1874. The natives, however, maintained themselves in the interior, inaccessible to the Dutch troops, and carried on a guerilla warfare. General van der Hoyden appeared to have subdued them in 1878-81, but they broke out again in 1896 under the traitor Taku Umar, who had been in alliance with the Dutch. He died shortly afterwards, but the trouble was not ended. General van Hentsz carried on a successful campaign in 1898 seq., but in 1901, the principal Achinese chiefs on the north coast having surrendered, the pretender-sultan fled to the Gajoes, a neighbouring inland people. Several expeditions involving heavy fighting were necessary against these in 1901-4, and a certain amount of success was achieved, but the pretender escaped, revolt still smouldered and hostilities were continued.

See P. J. Vein, Atchini en zijne betrekkingen tot Nederland (Leyden, 1873); J. A. Kruijt, Atjeh en de Atjehers (Leyden, 1877); Kielstra, Beschrijving van dcn Atjeh-oorlog (The Hague, 1883); Van Langen, Atjeh's Wesskust, Tijdschrift Aardrjjko, Genotktsch. (Amsterdam, 1888), p. 226; Renaud, Jaarboek van het Mynwezen (1882); J. Jacobs, Het famille-en Kampongleven op Groot Atjeh (Leyden, 1894); C. Snouck Hurgronje, De Atjehers (Batavia, 1894).

ACHOLI, a negro people of the upper Nile valley, dwelling on the east bank of the Bahr-el-Jebel, about a hundred miles north of Albert Nyanza. They are akin to the Shilluks of the White Nile. They frequently decorate the temples or cheeks with wavy or zigzag scars, and also the thighs with scrolls; some pierce the ears. Their dwelling-places are circular huts with a high peak, furnished with a mud sleeping-platform, jars of grain and a sunk fireplace. The interior walls are daubed with mud and decorated with geometrical or conventional designs in red, white or grey. The Acholi are good hunters, using nets and spears, and keep goats, sheep and cattle. In war they use spears and long, narrow shields of giraffe or ox hide. Their dialect is closely allied to those of the Alur, Lango and ja-Luo tribes, all four being practically pure Nilotic. Their religion is a vague fetishism. By early explorers the Acholi were called Shuli, a name now obsolete.

ACHROMATISM (Gr. a-, privative, chroma, colour), in optics, the property of transmitting white light, without decomposing it into the colours of the spectrum; "achromatic lenses'' are lenses which possess this property. (See LENS, ABERRATION and PHOTOGRAPHY.)

ACID (from the Lat. root ac-, sharp; acere, to be sour), the name loosely applied to any sour substance; in chemistry it has a more precise meaning, denoting a substance containing hydrogen which may be replaced by metals with the formation of salts. An acid may therefore be regarded as a salt of hydrogen. Of the general characters of acids we may here notice that they dissolve alkaline substances, certain metals, &c., neutralize alkalies and redden many blue and violet vegetable colouring matters.

The ancients probably possessed little knowledge indeed of acids. Vinegar (or impure acetic acid), which is produced when wine is allowed to stand, was known to both the Greeks and Romans, who considered it to be typical of acid substances; this is philologically illustrated by the words oxus, acidus, sour, and oxos, acetus, vinegar. Other acids became known during the alchemistic period; and the first attempt at a generalized conception of these substances was made by Paracelsus, who supposed them to contain a principle which conferred the properties of sourness and solubility. Somewhat similar views were promoted by Becher, who named the principle acidum primogenium, and held that it was composed of the Paracelsian elements "earth'' and "water.'' At about the same time Boyle investigated several acids; he established their general reddening of litmus, their solvent power of metals and basic substances, and the production of neutral bodies, or salts, with alkalies. Theoretical conceptions were revived by Stahl, who held that acids were the fundamentals of all salts, and the erroneous idea that sulphuric acid was the principle of all acids.

The phlogistic theory of the processes of calcination and combustion necessitated the view that many acids, such as those produced by combustion, e.g. sulphurous, phosphoric, carbonic, &c., should be regarded as elementary substances. This principle more or less prevailed until it was overthrown by Lavoisier's doctrine that oxygen was the acid-producing element; Lavoisier being led to this conclusion by the almost general observation that acids were produced when non-metallic elements were burnt. The existence of acids not containing oxygen was, in itself, sufficient to overthrow this idea, but, although Berthollet had shown, in 1789, that sulphuretted hydrogen (or hydrosulphuric acid) contained no oxygen, Lavoisier's theory held its own until the researches of Davy, Gay-Lussac and Thenard on hydrochloric acid and chlorine, and of Gay-Lussac on hydrocyanic acid, established beyond all cavil that oxygen was not essential to acidic properties.

In the Lavoisierian nomenclature acids were regarded as binary oxygenated compounds, the associated water being relegated to the position of a mere solvent. Somewhat similar views were held by Berzelius, when developing his dualistic conception of the composition of substances. In later years Berzelius renounced the "oxygen acid'' theory, but not before Davy, and, almost simultaneously, Dulong, had submitted that hydrogen and not oxygen was the acidifying principle. Opposition to the "hydrogen-acid'' theory centred mainly about the hypothetical radicals which it postulated; moreover, the electrochemical theory of Berzelius exerted a stultifying influence on the correct views of Davy and Dulong. In Berzelius' system potassium sulphate is to be regarded as K2O+.SO3-; electrolysis should simply effect the disruption of the positive and negative components, potash passing with the current, and sulphuric acid against the current. Experiment showed, however, that instead of only potash appearing at the negative electrode, hydrogen is also liberated; this is inexplicable by Berzelius's theory, but readily explained by the "hydrogen-acid'' theory. By this theory potassium is liberated at the negative electrode and combines immediately with water to form potash and hydrogen.

Further and stronger support was given when J. Liebig promoted his doctrine of polybasic acids. Dalton's idea that elements preferentially combined in equiatomic proportions had as an immediate inference that metallic oxides contained one atom of the metal to one atom of oxygen, and a simple expansion of this conception was that one atom of oxide combined with one atom of acid to form one atom of a neutral salt. This view, which was specially supported by Gay-Lussac and Leopold Gmelin and accepted by Berzelius, necessitated that all acids were monobasic. The untenability of this theory was proved by Thomas Graham's investigation of the phosphoric acids; for he then showed that the ortho- (ordinary), pyro- and metaphosphoric acids contained respectively 3, 2 and 1 molecules of "basic water'' (which were replaceable by metallic oxides) and one molecule of phosphoric oxide, P2 O5. Graham's work was developed by Liebig, who called into service many organic acids—-citric, tartaric, cyanuric, comenic and meconic—-and showed that these resembled phosphoric acid; and he established as the criterion of polybasicity the existence of compound salts with different metallic oxides. In formulating these facts Liebig at first retained the dualistic conception of the structure of acids; but he shortly afterwards perceived that this view lacked generality since the halogen acids, which contained no oxygen but yet formed salts exactly similar in properties to those containing oxygen, could not be so regarded. This and other reasons led to his rejection of the dualistic hypothesis and the adoption, on the ground of probability, and much more from convenience, of the tenet that "acids are particular compounds of hydrogen, in which the latter can be replaced by metals''; while, on the constitution of salts, he held that "neutral salts are those compounds of the same class in which the hydrogen is replaced by its equivalent in metal. The substances which we at present term anhydrous acids (acid oxides) only become, for the most part, capable of forming salts with metallic oxides after the addition of water, or they are compounds which decompose these oxides at somewhat high temperatures.''

The hydrogen theory and the doctrine of polybasicity as enunciated by Liebig is the fundamental characteristic of the modern theory. A polybasic acid contains more than one atom of hydrogen which is replaceable by metals; moreover, in such an acid the replacement may be entire with the formation of normal salts, partial with the formation of acid salts, or by two or more different metals with the formation of compound salts (see SALTS). These facts may be illustrated with the aid of orthophosphoric acid, which is tribasic:— Acid. Normal salt. Acid salts. H3PO4 Ag3PO4 Na2HPO4; NaH2PO4 Phosphoric Silver phosphate. Acid sodium acid. phosphates. Compound salts. Mg(NH4)PO4; Na(NH4)HPO4. Magnesium ammonium Microcosmic phosphate; salt. Reference should be made to the articles CHEMICAL ACTION, THERMOCHEMISTRY and SOLUTIONS, for the theory of the strength or avidity of acids.

Organic Acids.—-Organic acids are characterized by the presence of the monovalent group—CO.OH, termed the carboxyl group, in which the hydrogen atom is replaceable by metals with the formation of salts, and by alkyl radicals with the formation of esters. The basicity of an organic acid, as above defined, is determined by the number of carboxyl groups present. Oxy-acids are carboxyllc acids which also contain a hydroxyl group; similarly we may have aldehyde-acids, ketone-acids, &c. Since the more important acids are treated under their own headings, or under substances closely allied to them, we shall here confine ourselves to general relations.

Classification.—It is convenient to distinguish between aliphatic and aromatic acids; the first named being derived from open-chain hydrocarbons, the second from ringed hydrocarbon nuclei. Aliphatic monobasic acids are further divided according to the nature of the parent hydrocarbon. Methane and its homologues give origin to the "paraffin'' or "fatty series'' of the general formula Cn H2n+1COOH, ethylene gives origin to the acrylic acid series, CnH2n-1COOH, and soon. Dibasic acids of the paraffin series of hydrocarbons have the general formula CnH2(COOH)2n; malonic and succinic acids are important members. The isomerism which occurs as soon as the molecule contains a few carbon atoms renders any classification based on empirical molecular formulae somewhat ineffective; on the other hand, a scheme based on molecular structure would involve more detail than it is here possible to give. For further information, the reader is referred to any standard work on organic chemistry. A list of the acids present in fats and oils is given in the article OILS.

Syntheses of Organic Acids.—-The simplest syntheses are undoubtedly those in which a carboxyl group is obtained directly from the oxides of carbon, carbon dioxide and carbon monoxide. The simplest of all include: (1) the synthesis of sodium oxalate by passing carbon dioxide over metallic sodium heated to 350 deg. -360 deg. ; (2) the synthesis of potassium formate from moist carbon dioxide and potassium, potassium carbonate being obtained simultaneously; (3) the synthesis of potassium acetate and propionate from carbon dioxide and sodium methide and sodium ethide; (4) the synthesis of aromatic acids by the interaction of carbon dioxide, sodium and a bromine substitution derivative; and (5) the synthesis of aromatic oxy-acids by the interaction of carbon dioxide and sodium phenolates (see SALICYLIC ACID). (Carbon monoxide takes part in the syntheses of sodium formate from sodium hydrate, or soda lime (at 200 deg. -220 deg. ), and of sodium acetate and propionate from sodium methylate and sodium ethylate at 160 deg. —200 deg. . Other reactions which introduce carboxyl groups into aromatic groups ave: the action of carbonyl chloride on aromatic hydrocarbons in the presence of aluminium chloride, acid-chlorides being formed which are readily decomposed by water to give the acid; the action of urea chloride Cl.CO.NH2, cyanuric acid (CONH)3, nascent cyanic acid, or carbanile on hydrocarbons in the presence of aluminium chloride, acid-amides being obtained which are readily decomposed to give the acid. An important nucleus-synthetic reaction is the saponification of nitriles, which may be obtained by the interaction of potassium cyanide with a halogen substitution derivative or a sulphonic acid.

Acids frequently result as oxidation products, being almost invariably formed in all cases of energetic oxidation. There are certain reactions, however, in which oxidation can be successfully applied to the synthesis of acids. Thus primary alcohols and aldehydes, both of the aliphatic and aromatic series, readily yield on oxidation acids containing the same number of carbon atoms. These reactions may be shown thus:- R.CH2OH -> R.CHO -> R.CO.OH. In the case of aromatic aldehydes, acids are also obtained by means of "Cannizzaro's reaction'' (see BENZALDEHYDE). An important oxidation synthesis of aromatic acids is from hydrocarbons with aliphatic side chains; thus toluene, or methylbenzene, yields benzoic acid, the xylenes, or dimethyl-benzene, yield methyl-benzoic acids and phthalic acids. Ketones, secondary alcohols and tertiary alcohols yield a mixture of acids on oxidation. We may also notice the disruption of unsaturated acids at the double linkage into a mixture of two acids, when fused with potash.

In the preceding instances the carboxyl group has been synthesized or introduced into a molecule; we have now to consider syntheses from substances already containing carboxyl groups. Of foremost importance are the reactions termed the malonic acid and the aceto-acetic ester syntheses; these are discussed under their own headings. The electrosyntheses call for mention here. It is apparent that metallic salts of organic acids would, in aqueous solution, be ionized, the positive ion being the metal, and the negative ion the acid residue. Esters, however, are not ionized. It is therefore apparent that a mixed salt and ester, for example KO2C.CH2.CH2.CO2C2H5, would give only two ions, viz. potassium and the rest of the molecule. If a solution of potassium acetate be electrolysed the products are ethane, carbon dioxide, potash and hydrogen; in a similar manner, normal potassium succinate gives ethylene, carbon dioxide, potash and hydrogen; these reactions may be represented:- CH3.CO2 K CH3 CO2 K* CH2.CO K CH2 CO2 K. -> + + -> + + CH3.CO2 K CH3 CO2 K* CH2.CO K CH2 CO2 K. By electrolysing a solution of potassium ethyl succinate, KO2C.(CH2)2CO2C2H5, the KO2C. groups are split off and the two residues .(CH2)2CO2C2H5 combine to form the ester (CH2)4(CO2C2H5)2. In the same way, by electrolysing a mixture of a metallic salt and an ester, other nuclei may be condensed; thus potassium acetate and potassium ethyl succinate yield CH3.CH2.CH2.CO2C2H5.

Reactions.—Organic acids yield metallic salts with bases, and ethereal salts or esters (q.v.), R.CO.OR', with alcohols. Phosphorus chlorides give acid chlorides, R.CO.Cl, the hydroxyl group being replaced by chlorine, and acid anhydrides, (R.CO)2O, a molecule of water being split off between two carboxyl groups. The ammonium salts when heated lose one mobecule of water and are converted into acid-amides, R.CO.NH2, which by further dehydration yield nitriles, R.CN. The calcium salts distilled with calcium formate yield aldehydes (q.v.); distilled with soda-lime, ketones (q.v.) result.

ACIDALIUS, VALENS (1567-1595), German scholar and critic, was born at Wittstock in Brandenburg. After studying at Rostock, Grelfswald and Helmstedt, and residing about three years in Italy, he settled at Breslau, where he is said to have embraced the Roman Catholic religion. Early in 1595 he accepted an invitation to Neisse, about fifty miles from Breslau, where he died of brain fever on the 25th of May, at the age of twenty-eight. His excessive application to study, and the attacks made upon him in connexion with a pamphlet of which he was reputed the author, doubtless hastened his premature end. Acidalius wrote notes on Velleius Paterculus (1590), Curtius (1594), the panegyrists, Tacitus and Plautus, published after his death.

See Leuschner, Commeutatio de A. V. Vita, Moribus, et Scriptis (1757); F. Adam, "Der Neisser Rektor,'' in Bericht der Philomathic in Neisse (1872).

ACID-AMIDES, chemical compounds which may be considered as derived from ammonia by replacement of its hydrogen with acidyl residues, the substances produced being known as primary, secondary or tertiary amides, according to the number of hydrogen atoms replaced. Of these compounds, the primary amides of the type R.CO.NH2 are the most important. They may be prepared by the dry distillation of the ammonium salts of the acids (A. W. Hofmann, Ber., 1882, 15, p. 977), by the partial hydrolysis of the nitriles, by the action of ammonia or ammonium carbonate on acid chlorides or anhydrides, or by heating the esters (q.v.) with ammonia. They are solid crystalline compounds (formamide excepted) which are at first soluble in water, the solubility, however, decreasing as the carbon content of the molecule increases. They are easily hydrolysed, breaking up into their components when boiled with acids or alkanes. They form compounds with hydrochloric acid when this gas is passed into their ethereal solution; these compounds, however, are very unstable, being readily decomposed by water. On the other hand, they show faintly acid properties since the hydrogen of the amide group can be replaced by metals to give such compounds as mercury acetamide (CH3CONH)2Hg. Nitrous acid decomposes them, with elimination of nitrogen and the formation of the corresponding acid, RCO.NH2 + ONOH = R.COOH + N2 + H2O. When distilled with phosphoric anhydride they yield nitriles. By the action of bromine and alcoholic potash on the amides, they are converted into amines containing one carbon atom less than the original amide, a reaction which possesses great theoretical importance (A. W. Hofmann), R.CONH2 -> R.CONHBr -> R.NH2 + K2CO3 + KBr + H2O. Formamide, H.CONH2, is a liquid readily soluble in water, boillng at about 195 deg. C. with partial decomposition. Acetamide, CH3.CONH2, is a white deliquescent crystalline solid, which melts at 82-83 deg. C. and boils at 222 deg. C. It is usually prepared by distilling ammonium acetate. It is readily soluble in water and alcohol, but insoluble in ether. Benzamide, C6H5.CONH2, crystallizes in leaflets which melt at 130 deg. C. It is prepared by the action of ammonium carbonate on benzoyl chloride. It yields a silver salt which with ethyl iodide forms benzimidoethyl ether, C6H5C: (NH).OC2H5, a behaviour which points to the silver salt as being derived from the tautomeric imidobenzoic acid, C6H5C: (NH).OH (J. Tafel, Ber., 1890, 23, p. 104). On the preparation of the substituted amides from the corresponding sodamides see A. W. Titherley (Journ. Chem. Soc., 1901, 59, p. 391). The secondary and tertiary amides of the types (RCO)2NH and (RCO)3N may be prepared by heating the primary amides or the nitriles with acids or acid anhydrides to 200 deg. C. Thiamides of the type R.CSNH2 are known, and result by the addition of sulphuretted hydrogen to the nitriles, or by the action of phosphorus pentasulphide on the acid-amides. They readily decompose on heating, and are easily hydrolysed by alkanes; they possess a somewhat more acid character than the acid-amides.

ACINACES (from the Greek), an ancient Persian sword, short and straight, and worn, contrary to the Roman fashion, on the right side, or sometimes in front of the body, as shown in the bas-reliefs found at Persepolis. Among the Persian nobility it was frequently made of gold, being worn as a badge of distinction. The acinaces was an object of religious worship with the Scythians and others (Herod. iv. 62).

ACINETA (so named by C. G. Ehrenberg), a genus of suctorial Infusoria characterized by the possession of a stalk and cup-shaped sheath or theca for the body, and endogenous budding. O. Butschli has separated off the genus Metacineta (for A. mystacina), which reproduces by direct bud-fission.

ACINUS (Lat. for a berry), a term in botany applied to such fruits as the blackberry or raspberry, composed of small seedlike berries, and also to those berries themselves, or to grapestones. By analogy, acinus is applied in anatomy to similar granules or glands, or lobules of a gland.

ACIREALE, a town and episcopal see of the province of Catania, Sicily; from the town of the same name it is distant 9 m. N. by E. Pop. (1901) 35,418. It has some importance as a thermal station, and the springs were used by the Romans. It takes its name from the river Acis, into which, according to the legend, Acis, the lover of Galatea, was changed after he had been slain by Polyphemus. The rocks which Polyphemus hurled at Ulysses are identified with the seven Scogli de' Ciclopi, or Faraglioni, a little to the south of Acireale.

ACIS, in Greek mythology, the son of Pan (Faunus) and the nymph Syntaethis, a beautiful shepherd of Sicily, was the lover of the Nereid Galatea. His rival the Cyclops Polyphemus surprised them together, and crushed him to pieces with a rock. His blood, gushing forth from beneath, was metamorphosed by Galatea into the river bearing his name (now Fiume di Jaci), which was celebrated for the coldness of its waters (Ovid, Met. xiii. 750; Silius Italicus, Punica, xiv. 221).

ACKERMAN, FRANCIS (c. 1335—1387), Flemish soldier and diplomatist, was born at Ghent, and about 1380 became prominent during the struggle between the burghers of that town and Louis II. (de Male), count of Flanders. He was partly responsible for inducing Philip van Artevelde to become first captain of the city of Ghent in 1382, and at the head of some troops scoured the surrounding country for provisions and thus saved Ghent from being starved into submission. By his diplomatic abilities he secured the assistance of the citizens of Brussels, Louvain and Liege, and, having been made admiral of the Flemish fleet, visited England and obtained a promise of help from King Richard II. After Artevelde's death in November 1382, he acted as leader of the Flemings, gained several victories and increased his fame by skilfully conducting a retreat from Damme to Ghent in August 1385. He took part in the conclusion of the treaty of peace between Ghent and Philip the Bold, duke of Burgundy, the successor of Count Louis, in December 1385. Trusting in Philip, and ignoring the warnings of his friends, Ackerman remained in Flanders, and was murdered at Ghent on the 22nd of July 1387, leaving a memory of chivalry and generosity.

See Jean Froissart, Chroniques, edited by S. Luce and G. Raynaud (Paris, 1869-1897); Johannes Brandon, Chronodromon, edited hy K. de Lettenhove in the Chroniques rotatives a L'histoire de La Belgique sous la domination des ducs de Bourgogne (Brussels, 1870).

ACKERMANN, JOHANN CHRISTIAN GOTTLIEB (1756-1801), German physician, was born at Zeillenroda, in Upper Saxony, on the 17th of February 1756, and died at Altdorf on the 9th of March 1801. At the age of fifteen he became a student of medicine at Jena under E. G. Baldinger, whom he followed to Gottingen in 1773, and afterwards he studied for two years at Halle. A few years' practice at Stendal (1778-1799), where there were numerous factories, enabled him to add many valuable original observations to his translation (1780-1783) of Bernardino Ramazzini's (1633-1714) treatise on diseases of artificers. In 1786 he became professor of medicine at the university of Altdorf, in Franconia, occupying first the chair of chemistry, and then, from 1794 till his death in 1801, that of pathology and therapeutics. He wrote Institutiones Historiae Medicinae (Nuremberg, 1792) and Institutiones Therapiae Generalls (Nuremberg and Altdorf, 1784-1795), besides various handbooks and translations.

ACKERMANN, LOUISE VICTORINE CHOQUET (1813-1890), French poet, was born in Paris on the 30th of November 1813. Educated by her father in the philosophy of the Encyclopaedists, Victorine Choquet went to Berlin in 1838 to study German, and there married in 1843 Paul Ackermann, an Alsatian philologist. After little more than two years of happy married life her husband died, and Madame Ackermann went to live at Nice with a favourite sister. In 1855 she published Contes en vers, and in 1862 Contes et poesies. Very different from these simple and charming contes is the work on which Madame Ackermann's real reputation rests. She published in 1874 Poesies, premieres poesies, poesies philosophiques, a volume of sombre and powerful verse, expressing her revolt against human suffering. The volume was enthusiastically reviewed in the Revue des deux mondes for May 1871 by E. Caro, who, though he deprecated the impiete desesperee of the verses, did full justice to their vigour and the excellence of their form. Soon after the publication of this volume Madame Ackermann removed to Paris,where she gathered round her a circle of friends, but published nothing further except a prose volume, the Pensees d'un solitaire (1883), to which she prefixed a short autobiography. She died at Nice on the 2nd of August 1890.

See also Anatole France, La vie litteraire, 4th series (1892); the comte d'Haussonville, Mme. Ackermann (1882); M. Citoleux, La poesie philosophique au XIXe. siecle (vol. i., Mme. Ackermann d'apres de nombreux documents inedits, Paris, 1906).

ACKERMANN, RUDOLPH (1764-1834), Anglo-German inventor and publisher, was born on the 20th of April 1764 at Schneeberg, in Saxony. He had been a saddler and coachbuilder in different German cities, Paris and London for ten years before, in 1795, he established a print-shop and drawing-school in the Strand. Ackermann set up a lithographic press, and applied it in 1817 to the illustration of his Repository of Arts, Literature, Fashions,; &c. (monthly until 1828 when forty volumes had appeared). Rowlandson and other distinguished artists were regular contributors. He also introduced the fashion of the once popular English Annuals, beginning in 1825 with Forget-me-not; and he published many illustrated volumes of topography and travel, The Microcosm of London (3 vols., 1808-1811), Westminster Abbey (2 vols., 1812), Pine Rhine (1820), The World in Miniature (43 vols., 1821—1826), &c. Ackermann was an enterprising man; he patented (1801) a method for rendering paper and cloth waterproof, erected a factory at Chelsea for the purpose and was one of the first to illuminate his own premises with gas. Indeed the introduction of lighting by gas owed much to him. After the battle of Leipzig Ackermann collected nearly a quarter of a million sterling for the German sufferers. He died at Finchley, near London, on the 30th of March 1834.

ACKNOWLEDGMENT (from the old acknow, a compound of on- and know, to know by the senses, which passed through the forms oknow, aknow and acknow; acknowledge is formed on analogy of "knowledge''), an admission that something has been given or done, a term used in law in various connexions. The acknowledgment of a debt, if in writing signed by the debtor or his agent, is sufficient to take it out of the Statutes of Limitations. The signature to a will by a testator, if not made in the presence of two witnesses, may be afterwards acknowledged in their presence. The acknowledgment by a woman married before 1882 of deeds for the conveyance of real property not her separate property, requires to be made by her before a judge of the High Court or of a county court or before a perpetual or special commissioner. Before such an acknowledgment can be received, the judge or commissioner is required to examine her apart from her husband, touching her knowledge of the deed, and to ascertain whether she freely and voluntarily consents to it. An acknowledgment to the right of the production of deeds of conveyance is an obligation on the vendor, when he retains any portion of the property to which the deeds relate, and is entitled to retain the deeds, to produce them from time to time at the request of the person to whom the acknowledgment is given, to allow copies to be made, and to undertake for their safe custody (Conveyancing Act 1881, s. 9). The term "acknowledgment'' is, in the United States, applied to the certificate of a public officer that an instrument was acknowledged before him to be the deed or act of the person who executed it. .

"Acknowledgment money'' is the sum paid in some parts of England by copyhold tenants on the death of the lord of the manor.

ACLAND, CHRISTIAN HENRIETTA CAROLINE (1750-1815), usually called Lady Harriet Acland, was born on the 3rd of January 1750, the daughter of the first earl of Ilchester. In 1770 she married John Dyke Acland, who as a member of parliament became a vigorous supporter of Lord North's policy towards the American colonies, and, entering the British army in 1774, served with Burgoyne's expedition as major in the 20th regiment of foot. Lady Hurriet accompanied her husband, and, when he was wounded at Ticonderoga, nursed him in his tent at the front. In the second battle of Saratoga Major Acland was again badly wounded and subsequently taken prisoner. Lady Harriet was determined to be with him, and underwent great hardship to accomplish her object, proving herself a courageous and devoted wife. A story has been told that being provided with a letter from General Burgoyne to the American general Gates, she went up the Hudson river in an open boat to the enemy's lines, arriving late in the evening. The American outposts threatened to fire into the boat if its occupants stirred, and Lady Hnrriet had to wait eight "dark and cold hours,'' until the sun rose, when she at last received permission to join her husband. Major Acland died in 1778, and Lady Harriet on the 21st of July 1815.

ACLAND, SIR HENRY WENTWORTH, BART. (1815-1900), English physician and man of learning, was born near Exeter on the 23rd of August 1815, and was the fourth son of Sir Thomas Dyke Acland (1787-1871). Educated at Harrow and at Christ Church, Oxford, he was elected fellow of All Souls in 1840, and then studied medicine in London and Edinburgh. Returning to Oxford, he was appointed Lee's reader in anatomy at Christ Church in 1845, and in 1851 Radcliffe librarian and physician to the Radcliffe infirmary. Seven years later he became regius professor of medicine, a post which he retained till 1894. He was also a curator of the university galleries and of the Bodleian Library, and from 1858 to 1887 he represented his university on the General Medical Council, of which he served as president from 1874 to 1887. Hn was created a baronet in 1890, and ten years later, on the 16th of October 1900, he died at his house in Broad Street, Oxford. Acland took a leading part in the revival of the Oxford medical school and in introducing the study of natural science into the university. As Lee's reader he began to form a collection of anatomical and physiological preparations on the plan of John Hunter, and the establishment of the Oxford University museum, opened in 1861, as a centre for the encouragement of the study of science, especially in relation to medicine, was largely due to his efforts. "To Henry Acland,'' said his lifelong friend, John Ruskin, "physiology was an entrusted gospel of which he was the solitary preacher to the heathen,'' but on the other hand his thorough classical training preserved science at Oxford from too abrupt a severance from the humanities. In conjunction with Dean Liddell, he revolutionized the study of art and archaeology, so that the cultivation of these subjects, for which, as Ruskin declared, no one at Oxford cared before that time, began to flourish in the university. Acland was also interested in questions of public health. He served on the royal commission on sanitary laws in England and Wales in 1869, and published a study of the outbreak of cholera at Oxford in 1854, together with various pamphlets on sanitary matters. His memoir on the topography of the Troad, with panoramic plan (1839), was among the fruits of a cruise which he made in the Mediterranean for the sake of his health.

ACME (Gr. akme, point), the highest point attainable; first used as an English word by Ben Jonson.

ACMITE, or AEGIRITE, a mineral of the pyroxene (q.v.) group, which may be described as a soda-pyroxene, being essentially a sodium and ferric metasilicate, NAFe(SiO3)2. In its crystallographic characters it is close to ordinary pyroxene (augite and diopside), being monoclinic and having nearly the same angle between the prismatic cleavages. There are, however, important differences in the optical characters: the birefringence of acmite is negative, the pleochroism is strong and the extinction angle on the plane of symmetry measured to the vertical axis is small (3 deg. -5 deg. ). (The hardness is 6-6 1/2, and the specific gravity 3.55. Crystals are elongated in the direction of the vertical axis, and are blackish green (aegirite) or dark brown (acmite) in colour. Being isomorphous with augite, crystals intermediate in composition between augite or diopside and aegirite are not uncommon, and these are known as aegirine-augite or aegirine-diopside.

Acmite is a characteristic constituent of igneous rocks rich in soda, such as nepheline-syenites, phonolites, &c. It was first discovered as slender crystals, sometimes a foot in length, in the pegmatite veins of the granite of Rundemyr, near Kongsbeig in Rorway, and was named by F. Stromeyer in 1821 from the Gr. akme, a point, in allusion to the pointed terminations of the crystals. Aegirite (named from Aegir, the Scandinavian sea-god) was described in 1835 from the elaeolite-syenite of southern Norway. Although exhibiting certain varietal differences, the essential identity of acmite and aegirite has long been established, but the latter and more recent name is pethaps in more general use, especially among petrologists.

ACNE, a skin eruption produced by inflammation of the sebaceous glands and hair follicles, the essential point in the disease being the plugging of the mouths of the sebaceous follicles by a "comedo,'' familiarly known as "blackhead.'' It is now generally acknowledged that the cause of this disease is the organism known as bacillus acnes. It shows itself in the form of red pimples or papules, which may become pustular and be attended with considerable surrounding irritation of the skin. This affection is likewise most common in early adult life, and occurs on the chest and back as well as on the face, where it may, when of much extent, produce considerable disfigurement. It is apt to persist for months or even years, but usually in time disappears entirely, although slight traces may remain in the form of scars or stains upon the skin. Eruptions of this kind are sometimes produced by the continued internal use of certain drugs, such as the iodide or bromide of potassium. In treating this condition the face should first of all be held over steaming water for several minutes, and then thoroughly bathed. The blackheads should next be removed, not with the finger-nail, but with an inexpensive little instrument known as the "comedo expressor.'' When the more noticeable of the blackheads have been expressed, the face should be firmly rubbed for three or four minutes with a lather made from a special soap composed of sulphur, camphor and balsam of Peru. Any lather remaining on the face at the end of this time should be wiped off with a soft handkerchief. As this treatment might give rise to some irritation of the skin, it should be replaced every fourth night by a simple application of cold cream. Of drugs used internally sulphate of calcium, in pill, 1/6 grain three times a day, is a very useful adjunct to the preceding. The patient should take plenty of exercise in the fresh air, a very simple but nourishing diet, and, if present, constipation and anaemia must be suitably treated.

Rosacea, popularly known as acne rosacea, is a more severe and troublesome disorder, a true dermatitis with no relation to the foregoing, and in most cases secondary to seborrhea of the scalp. It is characterized by great redness of the nose and cheeks, accompanied by pustular enlargements on the surface of the skin, which produce marked disfigurement. Although often seen in persons who live too freely, it is by no means confined to such, but may arise in connexion with disturbances of the general health, especially of the function of digestion, and in females with menstrual disorders. It is apt to be exceedingly intractable to treatment, which is here too, as in the preceding form, partly local and partly constitutional. Of internal remedies preparations of iodine and of arsenic are sometimes found of service.

ACOEMETI (Gr. akoimetos, sleepless), an order of Eastern monks who celebrated the divine service without intermission day or night. This was done by dividing the communities into choirs, which relieved each other by turn in the church. Their first monastery was established on the Euphrates, in the beginning of the 5th century, and soon afterwards one was founded in Constantinople. Here also, c. 460, was founded by the consular Studius the famous monastery of the Studium, which was put in the hands of the Acoemeti and became their chief house, so that they were sometimes called Studites. At Agaunum (St Maurice in the Valais) a monastery was founded by the Burgundian king Sigismund, in 515, in which the perpetual office was kept up; but it is doubtful whether this had any connexion with the Eastern Acoemeti.

The Constantinopolitan Acoemeti took a prominent part in the Christological controversies of the 5th and 6th centuries, at first strenuously opposing Acacius, patriarch of Constantinople, in his attempted compromise with the monophysites; but afterwards, in Justinian's reign, falling under ecclesiastical censure for Nestorian tendencies.

See the article in Dictionary of Christian Antiquities; Wetzer und Welte, Kirchenlexicon (2nd ed.); and Herzog-Hauck, Realencyklopadie (3rd ed.); also the general histories of the time. (E. C. B.)

ACOLYTE (Gr.akolouthos, follower), the last of the four minor orders in the Roman Church. As an office it appears to be of local origin, and is entirely unknown in the Eastern Church, with the exception of the Armenians who borrowed it from the West. Before the council of Nicaea (325) it was only to be found at Rome and Carthage. When in 251 Pope Cornelius, in a letter to Fabius of Antioch, mentions among the Roman clergy forty-two acolytes, placing them after the subdeacons and before the other minor officials (see Eusebius, Hist. Ecc. lib. v. cap. 43), he gives no hint that the office was a new one, but speaks of them as holding an already established position. Their institution has therefore to be sought for at an earlier date than his pontificate. It is possible that the Liber Pontificalis refers to the office under the Latin synonym, when it says of Pope Victor (186—197) that he made sequentes cleros, a term—-sequens—-which Pope Gaius (283—293) uses in the sense of acolyte. While the office was well known in Rome, there is nothing to prove that it was also an order through which, as to-day, every candidate to the priesthood must pass. The contrary is a fact proved by many monumental inscriptions and authentic statements. Though the office is found at Carthage, and St Cyprian (200?-258) makes many references to acolytes, whom he used to carry his letters, this seems to be the only place in Africa where they were known. Tertullian, while speaking of readers and exorcists, says nothing about acolytes; neither does St Augustine. The Irish Church did not know them; and in Spain the council of Toledo (400) makes no mention either of the office or of the order. The Statuta Ecclesiae Antiqua (falsely called the Canons of the Fourth Council of Carthage in 397), a Gallican collection, originating in the province of Arles at the beginning of the 6th century, mentions the acolyte, but does not give, as in the case of the other orders, any form for the ordination. The Roman books are silent, and there is no mention of it in the collection known as the Leonine Sacramentary; while in the so-called Gelasian Massbook, which as we have it, is full of Gallican additions made to St Gregory's reform, there is the same silence, though in one MS. of the 10th century given by Muratori we find a form for the ordination of an acolyte. While there is frequent mention of the acolyte's office in the Ordines Romani, it is only in the Ordo VIII. (which is not earlier than the 7th century) that we find the very simple form for admitting an acolyte to his office. At the end of the mass the cleric, clad in chasuble and stole and bearing a linen bag on one arm, comes before the pope or bishop and receives a blessing. There is no collation of power or order but a simple admission to an office. The evidence available, therefore, points to the fact that the acolyte was only a local office and was not a necessary step or order for every candidate. In England, though the ecclesiastical organization came from Rome and was directed by Romans, we find no trace of such an office or order until the time of Ecgbert of York (767), the friand of Alcuin and therefore subject to Gallican influence. The Pontifical known as Ecgbert's shows that it was then in use both as an office and as an order, and Aelfric (1006) in both his pastoral epistle and canons mentions the acolyte. The conclusion, then, which seems warranted by the evidence, is that the acolyte was an office only at Rome, and, becoming an order in the Gallican Church, found its way as such into the Roman books at some period before the fusion of the two rites under Charlemagne.

The duties of the acolyte, as given in the Roman Pontifical, are identical with those mentioned in the Statuta Ecclesiae Antiqua of Arles: "It is the duty of acolytes to carry the candlesticks, to light the lamps of the church, to administer wine and water for the Eucharist.'' It might seem, from the number forty-two mentioned by Pope Cornelius, that at Rome the acolytes were divided among the seven ecclesiastical regions of the city; but we have no proof that, at that date, there were six acolytes attached to each region. From the ancient division of the Roman acolytes into Dalatini, or those in attendance on the pope at the Lateran palace, Stationarii, or those who served at the churches where there was a "station,'' and Regionarii, or those attached directly to the regiona, it would seem that the number forty-two was only the actual number then existing and not an official number. We get a glimpse of their duties from the Ordines Romani. When the pope rode in procession to the station an acolyte, on foot, preceded him, bearing the holy chrism; and at the church seven regionary acolytes with candles went before him in the procession to the altar, while two others, bearing the vessel that contained a pre-consecrated Host, presented it for his adoration. During the mass an acolyte bore the thurible (Ordo VI.) and three assisted at the washing of the hands. At the moment of communion the acolytes received in linen bags the consecrated Hosts to carry to the assisting priests. This office of bearing the sacrament is an ancient one, and is mentioned in the legend of Tarcisius, the Roman acolyte, who was martyred on the Appian Way while carrying the Hosts from the catacombs. The official dress of the acolyte, according to Ordo V., was a close-fitting linen garment (camisia) girt about him, a napkin hanging from the left side, a white tunic, a stole (orarium) and a chasuble (planeta) which he took off when he sang on the steps of the ambone.

At the present day, despite the earnest wish of the council of Trent (Sess. xxiii. cap. 17 d.r.), the acolyte, while remaining an order, has ceased to be essentially a clerical office, since the duties are now performed, almost everywhere, by laymen. The office has been revived, though unofficially, in the Church of England, as a result of the Tractarian movement.

See Morin, Commentarius in sacris Ecclesiae ordinationibus (Antwerp, 1685), ii. p. 209, iii. p. 152; Martene, De Antiquis Ecclesiae ritibus (Antwerp, 1739), ii. pp. 47 and 86; Mabillon, Musaeum Italicum II. for the Ordines Romani; Muratori, Liturgia Romana Vetus; Cabrol, Dictionnaire d'archeologie chretisnne et de liturgie, vol. i. col. 348-536.-. (E. TN.)

ACOMINATUS (AKOMINATOS), MICHAEL (c. 1140-1220), Byzantine writer and ecclesiastic, was born at Chonae (the ancient Colossae). At an early age he studied at Constantinople, and about 1175 was appointed archbishop of Athens. After the capture of Constantinople by the Franks and the establishment of the Latin empire (1204), he retired to the island of Coos, where he died. He was a versatile writer, and composed homilies, speeches and poems, which, with his correspondence, throw considerable light upon the miserable condition of Attica and Athens at the time. His memorial to Alexis III. Angelus on the abuses of Byzantine administration, the poetical lament over the degeneracy of Athens and the monodes on his brother Nicetas and Eustathius, archbishop of Thessalonica, deserve special mention.

Edition of his works by S. Lambros (1879—1880); Migne, Patrologia Graeca, cxl.; see also A. Ellissen, Michael Akominatos (1886), containing several pieces with German translation; F. Gregorovius, Geschichte der Stadt Athen im Mittelalter, i. (1889); G. Finlay, History of Greece, iv. pp. 133-134 (1877).

His younger brother NICETAS (Niketas), sometimes called CHONIATES, who accompanied him to Constantinople, took up politics as a career. He held several appointments under the Angelus emperors (amongst them that of "great logothete'' or chancellor) and was governor of the "theme'' of Philippopolis at a critical period. After the fall of Constantinople he fled to Nicaea, where he settled at the court of the emperor Theodorus Lascaris, and devoted himself to literature. He died between 1210 and 1220. His chief work is his History, in 21 books, of the period from 1180 to 1206. In spite of its florid and bombastic style, it is of considerable value as a record (on the whole impartial) of events of which he was either an eye-witness or had heard at first hand. Its most interesting portion is the description of the capture of Constantinople, which should be read with Villehardouin's and Paolo Rannusio's works on the same subject. The little treatise On the Statues destroyed by thc Latins (perhaps, as we have it, altered by a later writer) is of special interest to the archaeologist. His dogmatic work( Thesauros 'Orthodoxias, Thesaurus Orthodoxae Fidei), although it is extant in a complete form in MS., has only been published in part. It is one of the chief authorities for the heresies and heretical writers of the 12th century.

Editions: History, editio princeps, H. Wolf (1557); and in the Bonn Corpus Scriptorum Hist. Byz., 1st ed.,Bekker (1835); Rhetorical Pieces in C. Sathas, Mesaionike Bibliotheke, i. (1872); Thesaurus in Migne, Patrologia Graeca, cxxxix., cxl.; see also C. A. Sainte-Beuve, "Geoffroy de Villehardouin'' in Causeries du Lundi, ix.; S. Reinach, "La fin de l'empire grec'' in Esquisses Archeologiques (1888); C. Neumann, Griechische Geschichtsschreiber im 12. Jahrhundert (1888); Gibbon, Decline and Fall, ch. lx.; and (for both Michael and Nicetas) C. Krumbacher, Geschichte der byzantinischen Litteratur (1897).

ACONCAGUA, a small northern province of central Chile, bounded N. by Coquimbo, E. by Argentina, S. by Santiago and Valparaiso and W. by the Pacific. Its area is officially computed at 5487 sq. m. Pop. (1895) 113,165; (1902, official estimate based on civil registry returns) 131,255. The province is very mountainous, and is traversed from east to west by the broad valley of the Aconcagua river. The climate is hot and dry, the rainfall being too small to influence climatic conditions. The valleys are highly fertile, and where irrigation is employed large crops are easily raised. Beyond the limits of irrigation the country is semi-barren. Alfalfa and grapes are the principal products, and considerable attention is given to the cultivation of other fruits, such as figs, peaches and melons. The "Vale of Quillota,'' through which the railway passes between Valparaiso and Santiago, is celebrated for its gardens. The Aconcagua river rises on the southern slope of the volcano Aconcagua, flows eastward through a broad valley, or bay in the mountains, and enters the Pacific 12 m. north of Valparaiso. The river has a course of about 200 m., and its waters irrigate the best and most populous part of the province. Two other rivers—the Ligua and Choapa—traverse the province, the latter forming the northern boundary line. The capital is San Felipe, on the Aconcagua river; it had a population of 11,313 in 1895, and an estimated population of 11,660 in 1902. The other chief town is Santa Rosa de los Andes (est. pop. 6854), which is a principal station on the Transandine branch of the state railway. The only port in the province is Los Vilos, in lat. 32 deg. S., from which a railway 40 m. long runs north-east to the valley of the Choapa. Another short line connects Cabildo, in the valley of the Ligua, with the state railway.

ACONCIO, GIACOMO (1492-1566?), pioneer of religious toleration, was born at Trent, it is said, on the 7th of September 1492. He was one of the Italians like Peter Martyr and Bernardino Ochino who repudiated papal doctrine and ultimately found refuge in England. Like them, his revolt against Romanism took an extremer form than Lutheranism, and after a temporary residence in Switzerland and at Strassburg, he arrived in England soon after Elizabeth's accession. He had studied law and theology, but his profession was that of an engineer, and in this capacity he found employment with the English government. He was granted an annuity of L. 60 on the 27th of February 1560, and letters of naturalization on the 8th of October 1561 (Cal. State Papers, Dom. Ser., Addenda, 1547—1566, p. 495), and was for some time occupied with draining Plumstead marshes, for which object various acts of parliament were passed at this time (Lords' Journals, vol. i., and Commons' Journals, vol. i., passim). In 1564 he was sent to report on the fortifications of Berwick (Cal. St. Pap. For Ser. 1564-1565, passim; Acts P.C., 1558-1570, p. 146); his report is now in thc Record Office (C.S.P. For., 1564-1565, No. 512).