ISAR 204 ISCHYROMYS office, his utterances would commence in 758, 757, or 756 B. C. If the prophecies are arranged in the order of time, then chapters i-v would belong to an earlier period. Omitting these writings of un- certain date, the next utterances are in the reign of Ahaz, none apparently be- longing to the 16 years of Jotham's reign. He continued at least till the fourth year of King Hezekiah, 712 B. C, a period of 44 to 46 years. This is the minimum span of his prophecies; the maximum is much greater. Viewed as a poetic composition the book of Isaiah exhibits genius of a very high order. ISAR, or ISER {I'zer), a river of Bavaria, rises in the Tyrol, N. E. of Innsbruck, and flows 220 miles, generally in a N. and N. E. direction, till it falls into the Danube near Deggendorf. Munich and Landshut are on the banks "of Iser, rolling rapidly." Hohenlinden is 20 miles away. Area of its drainage basin, 3,545 square miles. ISATINE (I'za-ten), a product ob- tained by suspending finely powdered in- digo in three times its weight of boiling water, and adding gradually nitric acid of sp. gr. 1.35 till the blue color has dis- appeared. On cooling, crude isatine is deposited, and may be purified by dis- solving in potash, precipitating with hy- drochloric acid, and crystallizing from alcohol. It crystallizes in the form of brilliant yellowish-red prisms, which dis- solve readily in boiling water, in alcohol, and in ether. It may aso be produced synthetically by the action of oxidizing agents on amido-oxindol, or by the re- duction of orthonitro-phenyl glyoxalic acid in alkaline solution. Isatine does not unite with acids, but rather plays the part of an acid. It dissolves in potassic hydrate, forming a dark violet-colored solution of potassium isatine, which, on addition of argentic nitrate, gives car- mine-red crystals of argentine isatine, CsH,N02Ag. It also yields crystalline compounds, with alkaline hydric sul- phites. Boiled with concentrated nitric acid, it is converted first into nitro- salicylic acid, and finally into trinitro- phenol. When strongly heated, isatine fuses and sublimes in part unchanged. ISATIS (I'sa-tis), a genus of plants, order Brassicacess. I. tinctoria, the woad, is an annual plant, native of Eu- rope, occasionally cultivated here for the sake of its leaves, which yield a dye that may be substituted for indigo. It grows about four feet high, with large leaves clasping the stem with their broad bases; flowers yellow, large, in terminal racemes. ISATJRIA (is-or'e-a), in ancient geog- raphy, a district of Asia Minor, occupy- ing the summit and N. slopes of Mount Taurus. The people were stern and sav- age pirates and robbers. At length their depredations and those of their neigh- bors, the Cilicians, became so formidable that the Roman proconsul, P. Servilius, chased them into their mountain fast- nesses and coerced them into submission in 76 B. c, for which exploit he acquired the surname Isauricus. Nevertheless the Isaurians were not subdued, though Pom- pey drove them off the sea. They con- quered the Cilicians and remained the ter- ror of the neighboring states down to the 4th century. In the reign of the Emperor Gallienus (253-268) there even arose among this savage folk a rival emperor, Trebellianus, who, however, was finally crushed. This same jpeople also gave two emperors to Byzantium, Zeno I. (474- 491) and Leo III. (718-741); the de- scendants of the latter ruled over the em- pire of the East for three generations. From the 5th century onward the Isaur- ians gradually disappear from history. ISCHIA (is'ke-a), the ancient ^naria and Pithecusa, an island on the N. side of the entrance to the Bay of Naples, 6 miles from the mainland. Area, 26 square miles; pop. about 30,000. Ischia is a favorite place of summer resort, be- ing noted for the excellence of its warm mineral waters. Its highest point is the volcanic Monte Epomeo, 2,608 feet, the last outbreak of which occurred in 1302. In 1881 Casamicciola was nearly de- stroyed by two earthquake shocks. On Sept. 28, 1883, the town was utterly overwhelmed, only four or five buildings being left standing, and 4,000 or 5,000 persons lost their lives. The inhabitants grows fruits, wine, and olive oil, and carry on fishing. Chief towns: Ischia, a bishop's seat; Casamicciola, and Forio. ISCHIUM (is'ke-um), one of the bones in the pelvic arch in vertebrated animals. It forms the posterior and in- ferior part of the os innominatum, and bounds the obturator foramen in the lower half of its extent. ISCHL (ish'el), a town of Upper Aus- tria, on the river Traun, amid magnifi- cent Alpine scenery. It is the chief town of the district called the Salzkammergut. The situation of Ischl, and the saline baths established in 1822, attract 4,000 or 5,000 visitors annually. Pop. about 30,000. ISCHYROMYS (is-ker'o-mus) , the typical genus of the family Ischyromyi- das. It is known only by a North Ameri- can fossil rodent, I. typus, described by
