Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/235

Rh M A G M A G 217 be corrupted. They all had the power of punishing male factors with death. The chief among them was called archon, and the year took its designation from him, the archon eponymus, who was also constituted a sort of state protector of those who were unable to defend themselves. The Franks, Lombards, and Saxons appear to have been jealous of judicial authority, and averse to removing what concerned a man s private right out of the hands of his neighbours and equals ; every ten families are supposed to have had a magistrate of their own election, the tything man of England, the decanus of Trance and Lombardy. The decanus was the lowest species of judge. See Blackstone s Commentaries, 1825 ; Cowel, Laiv Diet., 1717 ; Gfiklart s Hallifax on the Civil Law, 1836 ; Hallam, Middle Ages. MAGLIABECHI, AXTONIO (1633-1 7H), one of the most remarkable bibliophiles of his time, was born at Florence, October 28, 1633, and followed the trade of a goldsmith until 1673, when he received the appointment of librarian to the grand-duke of Tuscany, a post for which he had qualified himself by his vast stores of self-acquired learning. He died on July 4, 1714, bequeathing his large private library to the grand-duke, who in turn handed it over to the city. See LIBRARIES, vol. xiv. pp. 530, 548. MAGNA CHARTA. See CHARTER, and ENGLAND, vol. viii. pp. 306, 308. MAGNA GR^CIA. See GR^CIA. MAGNESIA, in ancient geography, was the name of two cities in Asia Minor, both of considerable interest and importance. (1) A city of Ionia, situated on a small stream flowing into the valley of the Maeander, whence it was commonly called Magnesia ad Mnsandrum. It was distant 1 20 stadia or 1 5 Roman miles from Miletus, and rather less from Ephesus. According to tradition, as well as the similarity of names, it was founded by a body of colonists from the Thessalian tribe of the Magnetes, with whom were associated, accord ing to Strabo, some Cretan settlers. It was thus not properly an Ionic city, and for this reason apparently was not included among the cities of the Ionic league, though superior in wealth and prosperity to most of them, except Ephesus and Miletus. It was indeed taken and destroyed by the Cimmerians in their irruption into Asia Minor (about 660 B.C.), but was soon after rebuilt, and gradually recovered its former prosperity. It was one of the towns assigned by Artaxerxes to Themistocles for his support in his exile, and there the latter ended his days (449 B.C.). In later times it was chiefly noted for its temple of Artemis Leucophryne, which, according to Strabo, surpassed that at Ephesus in the beauty of its architecture, though inferior to it in size and wealth. The remains of this temple, as well as of the ancient city adjoining it, are still extant, and have been laid open by recent excavations. They are described by M. Texier (Asie Mineure, vol. iii.). Magnesia continued under the kings of Pergamum to be one of the most flourishing cities in this part of Asia, but appears to have gradually declined under the Roman empire, and its name disappears from history, though its continued exist ence is attested by coins as late as the time of Gallienus. (2) A city of Lydia, about 40 miles north-east of Smyrna, which stood on the southern bank of the river Hermus, at the foot of Mount Sipylus, from which circumstance it was often called for distinction s sake Magnesia ad Sipylum. It is probable from its name that it was founded, like the city of the same name in the valley of the Mreander, by Magnesian colonists from Thessaly ; but we have no authority for the fact. Nor is any mention of the town found in history till 190 B.C., when the Syrian king, Antiochus the Great, was defeated under its walls by the Roman consul L. Scipio, who derived from his success in this campaign the surname of Asiaticus. Magnesia became a city of importance under the Roman dominion, and, though nearly destroyed by an earthquake in the reign of Tiberius, was restored by that emperor, and continued to nourish throughout the period of the Roman empire. It was one of the few towns in this part of Asia Minor that retained its prosperity under the Turkish rule; and MANISA (q.v.) is at the present day a large and flourishing town with considerable trade. MAGNESIUM, a metallic element (symbol Mg) forming a basic oxide &quot; magnesia,&quot; MgO, which in some form or other is universally disseminated throughout the whole of the earth s crust, apart from the large masses of mineral con sisting essentially of magnesia compounds. This accounts for the presence of at least traces of magnesia in the ashes of all plants and animals, and for its presence in almost all natural waters. In these, however, it in general is present only as a quasi-contamination of the lime ; in certain mineral waters, on the other hand, known as bitter waters (as those of Epsom, Sedlitz, Piillna), sulphate of magnesia forms the principal solid component. All native chloride of sodium is accompanied by magnesia salts, including the cases of salt-springs and of ocean-water, the latter contain ing about 21 per cent, of magnesia as sulphate and chloride. Of magnesium minerals we may name the following: A. Silicates. (1) Olivine, SiO 2 .2MgO, occasionally met with in transparent crystals (&quot;chrysolite&quot;), but more fre quently embedded as an admixture in lava, basalt, and other rocks ; also in meteorites. (2) Augite and (3) horn blende, both MgO.SiO 2. The latter more frequently than the former forms independent rocks ; both occur abundantly as components of more ordinary mixed rocks, all basalts containing augite as a principal component. (4) Ser pentine, SiO 2 2H 2 O.3(Si0 2 .2MgO) + 2Aq (meaning 2H 2 O loosely combined), a very common mineral ; there are mountain masses consisting almost of it alone. In all these silicates, and more especially in (2) and (3), the MgO is partly replaced by FeO, CaO, MnO, and other isomorphous oxides, these latter not unfrequently even predominating over the MgO itself. Their names, in fact, represent genera of minerals comprising each numerous species. Asbestos (so remarkable on account of its exceptional structure, which lends itself for the production of fire-proof textile fabrics, paper, pasteboard, &amp;lt;fec.) must be mentioned here, as some varieties fall under hornblende, others under chrysotil (included in serpentine). More purely magnesian are (5) talc, 4SiO 2 .3MgO.H 2 O (Rammelsberg), and (6) meerschaum, 3Si0 2. 2MgO + 4(?)H 2 (same authority). B. Carbonates. Of these the most abundant are the dolomites, all compounds of the carbonates of lime and magnesia, a:Ca.(l -#)Mg.O.C0 2, where x may assume almost any value down to zero, which it actually has in &quot;magnesite,&quot; MgOC0 2. Bitter spar, MgOC0 2, is very similar to and isomorphous with Iceland spar, CaOC0. C. Soluble Salts, known chiefly as occurring in the famous salt-deposits of Stassfurth in Germany : kieserite, MgOS0 3 .H 2 O (Epsom salt minus 6H 2 0) ; carnallite, MgCl. 2 .KCl + 6H 2 O ; kainite, a hydrated compound of chlorides and sulphates of magnesium and potassium. Any of these minerals may be used, and A (4), B, and C are actually used for the preparation of magnesium compounds. Starting from magnesite, we need only sub ject it to gentle ignition to obtain the oxide MgO ; treat ment with dilute sulphuric or muriatic acid produces the sulphate (EPSOM SALT, q.v.) or the chloride, as a solution, contaminated in general, chiefly with iron, also with alumina, and perhaps lime. The two former, after peroxida- tion of the iron by chlorine, may be eliminated by digestion with powdered magnesite, and filtered off. The acidified muriate solution, on evaporation and cooling, deposits trans- XV. 28