Page:Encyclopædia Britannica, Ninth Edition, v. 1.djvu/169

Rh A D E A D I 153 Roman sepulchres have been found in the vicinity. The modern city has a clean appearance, but the situation is unhealthy. It is remarkable for the number of its con vents and nunneries, and has several churches, the chief of which is supported by beautiful pillars of polished lava. On the river Simeto, near the town, there is a series of beautiful cascades. Population, 12,999. ADERSBACH ROCKS, a remarkable group of isolated columnar rocks in a valley of the Riesengebirge, on the frontier of Bohemia and Prussian Silesia, 9 miles W.N.W. of Braunau. The mountain, for several miles, appears divided into detached masses by perpendicular gaps, varying in depth from 600 to 1200 feet. These masses are from a few feet to several hundred yards in diameter. The part called the labyrinth consists of smaller masses of columnar form, confusedly piled on one another, and rising to heights of from 100 to 200 feet. From their fantastic shapes the rocks have received various fanciful appellations. Some geologists have supposed that their remarkable structure is the result of subterranean commotion; but the generally- received opinion is, that the whole area had once been a tabular mass of sandstone of unequal hardness, and that the soft parts, which formed perpendicular seams, have been worn away by water and atmospheric changes, leaving the harder portions in their natural position. The recesses of this wild region frequently afforded a place of refuge to the distressed inhabitants of the district during the Thirty Years War. ADHESION, a term used to denote the physical force in virtue of which one body or substance remains attached to the surface of another with which it has been brought into contact. It is to be distinguished from cohesion, which is the mutual attraction that the particles of the same body exert on each other; and it differs from chemical attraction or affinity^ since the properties of the substances it affects remain unchanged after it takes place. It is a force that the molecules of the adhering bodies exert on each other, and must not be confounded with a contact which is due to mere mechanical pressure, such as that which a piece of caoutchouc tubing exerts by its elasticity on a body that distends it. A very familiar instance of adhesion occurs in the wetting of solid bodies. It often, indeed generally, happens that, when a solid and a liquid touch each other, a film of the latter adheres to the former, and neither falls nor can be shaken off. This arises from the adhesion of the liquid to the solid being a stronger force than the cohesion of the particles of the liquid. It is also stronger than the force of gravitation; and the liquid can only be removed by being forcibly rubbed off, or by the process of evaporation. The force of adhesion may be determined by poising a plate of metal on a balance, and afterwards ascertaining what additional force will be required to detach it from the surface of a liquid. But this can only be done in the few cases in which the liquid does not wet the solid (otherwise the measurement would be that of the cohesive force of the liquid), and does not act on it chemically. The phenomena of CAPILLARY ATTRACTION (q.v.) depend on adhesion. Sometimes, when a solid and a liquid are brought into contact, the adhesive force overcomes the cohesion of the particles of the solid, so that it loses its solid form, and is dissolved or held in solution. Solid bodies, too, as well as liquids, adhere to solids. Smooth surfaces (of lead, for instance, or of dissimilar metals) will adhere; and if two plates of polished glass be laid together, it will scarcely be possible to separate them without breaking them. If the solids are pressed together, the adhesive force is generally greater; but it has been shown to be dependent to a very slight extent only on the pressure of the atmosphere. To a looser kind of adhesion, whereby one body is prevented from moving smoothly on the surface of another, we give the name of friction. The force of this increases with pressure, which may be the effect of gravitation or the result of mechanical appliances. If it be desired that solids should adhere permanently, this is commonly enected by the intervention of other substances the cements, mortars, and solders in a liquid or viscid state, which, when they &quot;set&quot; or become solid, adhere closely to the bodies united by means of them. The principle of the processes of plating, gilding, &c., is similar to this. The adhesive force of cements, &c., is sometimes very great. The common experiment of splitting a thin sheet of paper into two is an illustration of it. The paper is pasted carefully between two pieces of cloth, which are pulled asunder after the paste has dried. The adhesion of the paste to- the paper and to the cloth is so strong that the paper is- thus separated into two sheets, which can easily be de tached from the cloth by wetting it. Again, air and other gases adhere to solids. A dry needle, placed carefully on the surface of still water, will float, resting on a cushion of air; and when thermometers are filled with mercury,, the liquid has to be boiled in them to expel the air that adheres to the glass. ADIAPHOR1STS (dStar^opo?, indifferent), a name ap plied to Melancthon and his supporters in a controversy which arose out of the so-called Leipsic Interim (154S) r and raged until 1555. In 1547 Charles V. had drawn up the Augsburg Interim, with a view to provide for the tem porary government of the Church until a general council could be called. This gave great dissatisfaction both to- the more advanced and to the more moderate reformers; and the object of Melancthon s Leipsic Interim was to- reconcile all parties, if possible, by declaring that certain rites and observances of the Roman Catholic Church and the jurisdiction of the Roman Catholic bishops being adiaphora (things indifferent), might be lawfully recognised. On the other hand, the Catholics were required to accept the Protestant formula of the doctrine of justification,, leaving out the words sola fide, which, it was said, might belong to the adiaphora. In the controversy that fol lowed, Melancthon s chief opponent was his former col league, Matth. Flacius, on whose removal from Wittenburg to Magdeburg the latter place became the head-quarters of the extreme Lutherans. ADIGE (German, Etscli), the ancient Athesis, a large river of Italy, formed by several rivulets which rise in the Rhaetian Alps, and unite near Glarus. After flowing eastward to the neighbourhood of Botzen, it receives the- Eisach, and becomes navigable. It then turns to th& south, and leaving the Tyrol, enters Lombardy 13 miles S. of Roveredo. After traversing Northern Italy in a course first southerly, but then easterly, it falls into the Adriatic at Porto-Fossone, a few miles N. of the Po. The most considerable towns on its banks are Trent and Roveredo- in the Tyrol, and Verona and Legnago in Italy. It is navigable from the heart of the Tyrol to the sea, and has in Lombardy a breadth of 200 yards and a depth of from 10&quot; to 1 6 feet, but the strength of the current renders its navi gation very difficult, and lessens its value as a means of transit between Germany and Northern Italy. The Adige has a course of about 220 miles. ADIPOCERE (from adeps, fat, and cera, wax), a sub stance into which animal matter is sometimes converted, deriving its name from the resemblance it bears to both fat and wax. When the Cemetery of the Innocents at Paris- was removed in 1786-87, great masses of this substance- were found where the coffins containing the dead bodies had been placed very closely together. At the bottom of the coffin, in these cases, there appeared, loosely enveloped in linen, a shapeless mass, of a dinev white colour, L 20