the posterior surface of the iris and the ciliary muscle. (See Eye.) It is rapidly resccreted if allowed to escape by any wound in the cornea.
AQUEOUS ROCKS. In geology, rocks which have been laid down as mechanical, chemi- cal, or organic deposits from water. They be- long to the sedimentary rocks. Avhich also include rocks deposited from air (seolian deposits).
I. The mechanical deposits from water are derived from the destruction of preexisting rocks. Rain and rivers move considerable quan- tities of disintegrated material, depositing it wherever the load is too great for the volume and velocity of the current. Waves, rolling against a shore, break from it small and large fragments, carry these fragments back with them, and deposit them in layers on the bottom of the basin. The coarse particles are left near- est the shore, forming conglomerate or gravel; finer particles are carried somewluit farther out, forming sand, which by cementation becomes sandstone, quartzite. novaeulite, or, when mixed with feldspar, arkose or graywacke : still finer particles are carried yet farther out and are <lcposited, to form mud or clay, which by cemen- tation or consolidation becomes mudstone, shale, or slate.
II. Chemical deposition from water may be due to the mingling of solutions, to changes in the temperature or pressure of water containing substances in solution, or to the simple evapora- tion of water. For convenience in discussion, chemical precipitates may be divided into three general classes: (a I precipitates of the alkalies and alkaline earths, giving calcareous tufa, sin- ter, travertine, stalactite, onyx marbles, oolite, gypsum, rock salt: (b) siliceous precipitates, giving chert (flint or hornstone), geyserite, sili- ceous sinter: (c) ferruginous precipitates, giv- ing iron ores. These latter are largely deposited through the aid of decaying vegetable matter, and might properly be considered under class III., but the deposition is due rather to the chemical efi'ect of dead organisms than to the activities of the living forms.
III. Organic deposits originate in the growth and decay of organisms, either in situ or after transportation. Deposits of this character are commonly made in water which is dee])er and quieter than that in which chemical deposits are made. They may be divided into— (a) cal- careous accumulations, resulting in shell marl, chalk, limestone, dolomite ; (b) siliceous accumu- lations, such as infusorial earth, siliceous ooze, some forms of flint or chert: (c) ferruginous ac- cumulations, resulting in certain bog ores: (d) carbonaceous accumulations, loiown as peat, lig- nite, browni coal, or coal.
Rocks of mechanical and organic deposition form the great mass of the aqueous rocks. The common order of occurrence from the shore outward — conglomerate, sandstone, mud, and limestone — corresponds in a general way with increase in depth of water. It follows, there- fore, that if at any point the body of water is transgressing on the land, resulting in deepen- ing of the water, the vertical order of super- position of mechanical deposits will be conglom- erate, sandstone, shale, and limestone ; and, vice versa, if the water is receding, the order will be reversed. 'I'lierc is thus a change of chara<-ter of the sediments in any series both laterally and vertically. The aqueous rocks of the earth's crust are found in such recurring successions and by their study the vertical oscillations of con- tinents and ocean have been determined. In a very general way, it may be said that the suc- cession of aqueous deposits during geological history has been much the same the world over. The members of this succession have been grouped into divisions on the basis of their order of superposition, their structure, and their contained fossils, and these divisions correspond to the time divisions of geological history. See Geology: Limestoxe: Lithogexesi.s.
AQUILA, a'kwe-la, Degli Auruzzi (It., Aquila of the Abruzzi). An episcopal city in south Italy, on the Tcrni-SoluKina Railway, 02 miles southeast of Terni (ilap: Italy, H 5). It is pleasantly situated on a hill beside the .verno ; the streets are broad, the houses pic- turesque, the churches numerous and interesting. It is a favorite summer resort for Italians. .s the meeting-point of roads leading to Apennine passes that have been compared to Thermopylae, it is of great strategic importance. Aquila was built about 1240 by the Emperor Frederick II. from the ruins of Anjiternum, the birthplace of Sallust, the Roman historian. In 1703 it was almost destroyed by an earthquake, in which two thousand persons perished. It has linen, leather, paper, and wool factories, and is an im- portant saffron market. Population, in 1881, 11,720: in 190], 21,188.
AQ'UILA, Greek Aversion of. See AQriL., PONTICCS.
AQUILA, ä'kwḗ-lȧ, Johann Kasper (1488-1560). A German Protestant reformer. He was
born in Augsburg, studied at Ulm and in Italy, and in 1515 was appointed chaplain to Franz von Sickingen. He accepted Lutheranism and was imprisoned, but was released, and while court chaplain to the Elector of Saxony at Wittenberg (1524-27), through his knowledge of Hebrew assisted Luther in translating the Bible.
Against the Interim (q.v.) he wrote Christliche Bedenken auf das Interim (1548), and Das Interim illuminiert (1548), for which a price was set on his head by Charles V. In 1552 he
was restored to his pastorate at Saalfeld, which
Luther had procured for him in 1527, and filled
that office until his death.
AQ'UILA, Ponticus, i.e., Aquila of Pontus (Lat. Aquila Ponticus) . A celebrated translator of the Old Testament into Greek, who flourished about A.D. 130. He lived in Palestine and seems to have been a pagan converted first to Christianity and subsequently to Judaism. He studied under the Jewish Rabbis, notably the celebrated Rabbi Akiba. His Greek version, fragments of which are preserved in Origen's Hexapla, was marked by an extreme literalness of translation: it was probably this literalness that made the Jews for a long time prefer the version of Aquila to the Septuagint translation. A recently found specimen of Aquila's translation has been published by F. C. Burkitt,
Fragments of the Book of Kings, according to the
translation of Aquila (Cambridge, 1897).
AQ'UILA'RIA. See Aloes Wood.
AQ'UILE'GIA. See RAKU.NCULACEJi.
AQUILEJA, a'kwe-lfi'ya (or Aglar, a-glilr', as it was called in the Middle Ages). A small towii of the Austrian crown-land of Gorz and
