by reduction with ammonium sulphide. Isatin dissolved in concentrated sulphuric acid gives a blue coloration with thiophene, due to the formation of indophenin (see Abst. J.C.S., 1907). Concentrated nitric acid oxidizes it to oxalic acid, and alkali fusion yields aniline. It dissolves in soda forming a violet solution, which soon becomes yellow, a change due to the transformation of sodium N-isatin into sodium isatate, the aci-isatin salt being probably formed intermediately (Heller, Abst. J.C.S., 1907, i. p. 442). Most metallic salts are N-derivatives yielding N-methyl ethers; the silver salt is, however, an O-derivative, yielding an O-methyl ether (A. v. Baeyer, 1883; W. Peters, Abst. J.C.S., 1907, i. p. 239).
|Isatin (ψ)||Sodium salt||Isatin||Silver Salt|
ISAURIA, in ancient geography, a district in the interior of Asia Minor, of very different extent at different periods. The permanent nucleus of it was that section of the Taurus which lies directly to south of Iconium and Lystra. Lycaonia had all the Iconian plain; but Isauria began as soon as the foothills were reached. Its two original towns, Isaura Nea and Isaura Palaea, lay, one among these foothills (Dorla) and the other on the watershed (Zengibar Kalé). When the Romans first encountered the Isaurians (early in the 1st century B.C.), they regarded Cilicia Trachea as part of Isauria, which thus extended to the sea; and this extension of the name continued to be in common use for two centuries. The whole basin of the Calycadnus was reckoned Isaurian, and the cities in the valley of its southern branch formed what was known as the Isaurian Decapolis. Towards the end of the 3rd century A.D., however, all Cilicia was detached for administrative purposes from the northern slope of Taurus, and we find a province called at first Isauria-Lycaonia, and later Isauria alone, extending up to the limits of Galatia, but not passing Taurus on the south. Pisidia, part of which had hitherto been included in one province with Isauria, was also detached, and made to include Iconium. In compensation Isauria received the eastern part of Pamphylia. Restricted again in the 4th century, Isauria ended as it began by being just the wild district about Isaura Palaea and the heads of the Calycadnus. Isaura Palaea was besieged by Perdiccas, the Macedonian regent after Alexander’s death; and to avoid capture its citizens set the place alight and perished in the flames. During the war of the Cilician and other pirates against Rome, the Isaurians took so active a part that the proconsul P. Servilius deemed it necessary to follow them into their fastnesses, and compel the whole people to submission, an exploit for which he received the title of Isauricus (75 B.C.). The Isaurians were afterwards placed for a time under the rule of Amyntas, king of Galatia; but it is evident that they continued to retain their predatory habits and virtual independence. In the 3rd century they sheltered the rebel emperor, Trebellianus. In the 4th century they are still described by Ammianus Marcellinus as the scourge of the neighbouring provinces of Asia Minor; but they are said to have been effectually subdued in the reign of Justinian. In common with all the eastern Taurus, Isauria passed into the hands of Turcomans and Yuruks with the Seljuk conquest. Many of these have now coalesced with the aboriginal population and form a settled element: but the district is still lawless.
This comparatively obscure people had the honour of producing two Byzantine emperors, Zeno, whose native name was Traskalisseus Rousoumbladeotes, and Leo III., who ascended the throne of Constantinople in 718, reigned till 741, and became the founder of a dynasty of three generations. The ruins of Isaura Palaea are mainly remarkable for their fine situation and their fortifications and tombs. Those of Isaura Nea have disappeared, but numerous inscriptions and many sculptured stelae, built into the houses of Dorla, prove the site. It was the latter, and not the former town, that Servilius reduced by cutting off the water supply. The site was identified by W. M. Ramsay in 1901. The only modern exploration of highland Isauria was that made by J. S. Sterrett in 1885; but it was not exhaustive.
Bibliography.—W. M. Ramsay, Historical Geography of Asia Minor (1890), and article “Nova Isaura” in Journ. Hell. Studies (1905); A. M. Ramsay, ibid. (1904); J. R. S. Sterrett, “Wolfe Expedition to Asia Minor,” Papers Amer. Inst. of Arch. iii. (1888); C. Ritter, Erdkunde, xix. (1859); E. J. Davis, Life in As. Turkey (1879). (D. G. H.)
ISCHIA (Gr. Πιθηκοῦσα, Lat. Aenaria, in poetry Inarime), an island off the coast of Campania, Italy, 16 m. S.W. of Naples, to the province of which it belongs, and 7 m. S.W. of the Capo Miseno, the nearest point of the mainland. Pop. about 20,000. It is situated at the W. extremity of the Gulf of Naples, and is the largest island near Naples, measuring about 19 m. in circumference and 26 sq. m. in area. It belongs to the same volcanic system as the mainland near it, and the Monte Epomeo (anc. Ἐπωπεύς, viewpoint), the highest point of the island (2588 ft.), lies on the N. edge of the principal crater, which is surrounded by twelve smaller cones. The island was perhaps occupied by Greek settlers even before Cumae; its Eretrian and Chalcidian inhabitants abandoned it about 500 B.C. owing to an eruption, and it is said to have been deserted almost at once by the greater part of the garrison which Hiero I. of Syracuse had placed there about 470 B.C., owing to the same cause. Later on it came into the possession of Naples, but passed into Roman hands in 326, when Naples herself lost her independence. The ancient town, traces of the fortifications of which still exist, was situated near Lacco, at the N.W. corner of the island. Augustus gave it back to Naples in exchange for Capri. After the fall of Rome it suffered attacks and devastations from the successive masters of Italy, until it was finally taken by the Neapolitans in 1299.
Several eruptions are recorded in Roman times. The last of which we have any knowledge occurred in 1301, but the island was visited by earthquakes in 1881 and 1883, 1700 lives being lost in the latter year, when the town of Casamicciola on the north side of the island was almost entirely destroyed. The hot springs here, which still survive from the period of volcanic activity, rise at a temperature of 147° Fahr. and are alkaline and saline; they are much visited by bathers, especially in summer. They were known in Roman times, and many votive altars dedicated to Apollo and the nymphs have been found. The whole island is mountainous, and is remarkable for its beautiful scenery and its fertility. Wine, corn, oil and fruit are produced, especially the former, while the mountain slopes are clothed with woods. Tiles and pottery are made in the island. Straw-plaiting is a considerable industry at Lacco; and a certain amount of fishing is also done. The potter’s clay of Ischia served for the potteries of Cumae and Puteoli in ancient times, and was indeed in considerable demand until the catastrophe at Casamicciola in 1883.
The chief towns are Ischia on the E. coast, the capital and the seat of a bishop (pop. in 1901, town, 2756; commune, 7012), with a 15th-century castle, to which Vittoria Colonna retired after the death of her husband in 1525; Casamicciola (pop. in 1901, town, 1085; commune, 3731) on the north, and Forīo on the west coast (pop. in 1901, town, 3640; commune, 7197). There is regular communication with Naples, both by steamer direct, and also by steamer to Torregaveta, 2 m. W.S.W. of Baiae and 121 m. W.S.W. of Naples, and thence by rail.
ISCHL, a market-town and watering-place of Austria, in Upper Austria, 55 m. S.S.W. of Linz by rail. Pop. (1900) 9646. It is beautifully situated on the peninsula formed by the junction of the rivers Ischl and Traun and is surrounded by high mountains, presenting scenery of the finest description. To the S. is the Siriuskogl or Hundskogl (1960 ft.), and to the W. the Schafberg (5837 ft.), which is ascended from St Wolfgang by a rack-and-pinion railway, built in 1893. It possesses a fine parish church, built by Maria Theresa and renovated in 1877–1880, and the Imperial Villa is surrounded by a magnificent park. Ischl is one of the most fashionable spas of Europe, being the favourite