Page:Encyclopædia Britannica, Ninth Edition, v. 15.djvu/503

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M A N M A N 479 and faithfully to bequeath it to him on his own death. Excommunicated in 1259 by Alexander IV., Manfred again resorted to arms, and overrunning the papal states, was made master of Tuscany by the battle of Monte Aperto (September 4, 1260). Now at the height of his power, he was anew excommunicated by Urban IV. in 1261, and in 1263 his forfeited crown was offered to Charles, count of Anjou, and brother of Louis IX. of France. Towards the end of summer in 1265, giving effect to a crusade proclaimed by Urban, Charles with his army entered Piedmont, but the encounter with the Sicilians did not take place until February 1266 at Benevento, where Manfred, filled with despair by the cowardly flight of his Apulians, spurred into the thickest of the battle and fell covered with wounds. His mangled body was hastily buried under a heap of stones near the bridge, but after wards, at the instance of Pope Clement IV., was dragged out and laid in unconsecrated ground on the frontier of the kingdom. MANFREDONIA, a seaport and city of Italy, in the province of Foggia, the see of an archbishop, and the centre of a maritime district, lies 22 miles north-east of Foggia, with which it is connected by railway. The situation, on the shores of the Gulf of Manfredonia and at the foot of Monte Gargano, is finely sheltered, and the vegetation of the district is similar to that of Sicily. A castle dating from the 13th century protects the port, and the city is sur rounded by walls and towers. The principal building is the cathedral. Though the anchorage is available only for small vessels, a fair trade is carried on in the export of grain. While in 1863 there entered in all 418 vessels with a total burden of 20,346 tons, in 1880 the burden of the 463 vessels was only 10,832 tons. The population of the commune in 1881 was 9401. Manfredonia is the historical representative of Sipontum, a Roman inunicipium and colony of some mark, which lay about 1 1 miles to the south. The ancient city having greatly declined, partly owing to the unhealthiness of its situation and partly to the disasters of war, Manfred transferred its inhabitants to the present site in 1261. For a time Manfredonia flourished greatly, but the ravages of the Turks in 1620 proved fatal to its development. The bite of Sipontum is marked by the ancient church of Santa Maria di Siponto. MANGALIA, a town on the coast of the Black Sea, in the south of the Dobrudja, at the head of a district in the new Roumanian province of Kustendji. In the time of Genoese supremacy in the Black Sea it was a place of 30,000 inhabitants ; and its population has again risen from a few hundreds to upwards of two thousand. According to the Corpus Inscriptiomim Latinarum, it is to be identified with the ancient Thracian city of Callatis (or Acervetis, as it was formerly called) a colony of Miletus which continued to be a flourishing place to the close of the Roman period. MANGALORE, the administrative headquarters of south Kanara district,. Madras, is situated on the Malabar coast, in 12 51 40" N. lat, 74 52 36" E. long., with a population in 1871 of 29,667. The town is picturesque, clean, and prosperous. The native houses are laid out in good streets, and the European quarter is particularly pleasant. Mangalore clears and exports all the coffee of Coorg, and trades directly with Arabia and the Persian Gulf. In 1875 3600 ships of 264,000 tons entered. The exports in that year were valued at 505,800, and the imports at 272,704. There is a large native Roman Catholic population, with two European bishops, several churches, and a convent. The Basel Lutheran mission has its headquarters here, and has done much good in teaching trades, &c. Good cloth is woven at their establishment ; the making of roof tiles, printing, and bookbinding are also taught. MANGANESE, a metallic chemical element (symbol Mn ; atomic weight 55) widely diffused throughout the mineral kingdom, being an almost constant companion of ferrous oxide, lime, and magnesia in their native carbonates and silicates. Of manganese minerals proper which are comparatively scarce the most important is pyrolusite, the native binoxide, MnO 2 . This is a black crystalline or crystallized solid with semi-metallic lustre, sufficiently soft to give a (black) streak on paper; hardness, 2 to 2-5: specific gravity, 4/8 to 4-9. It is known in commerce as "black oxide of manganese" or " manganese," and is extensively used for the industrial extraction of chlorine from muriatic acid. Its most extensive beds are found at Ilmenau and Elgersburg, Thuringia; near Giessen, North Hesse; near Ma hrisch-Triibau, Moravia; and in Spain. Almost all pyrolusite is contaminated with more or less of the following "manganites" general formula MnO 2 .R"O which besides occur (in the same localities) as independent minerals: Iraimite, Mn 2 O 3 or MnO 2 MnO; manganite, or grey manganese ore, Mn 2 O 3 .H 2 O; liausman- nite, Mn 3 O 4 or MnO 2 .2MnO ; and psilomelan, a complex mineral, the composition of which generally approximates. to 4Mn0 2 .RO + a?H 2 O, the R being chiefly Ba or K 2 , but including in general more or less of Ca, Mg, and Mn. These ores "are not unlike pyrolusite in their general appearance, but can usually be easily distinguished from it by their greater hardness and other physical pro perties. Closely allied to psilomelan are those earthy, massive, or reniform mineral mixtures known as " bog- manganese," "cupreous manganese," "earthy cobalt." In the two last-named the RO is chiefly CuO and CoO respec tively. We must here mention those curious formations known as " manganese nodules " which were so frequently dredged up by the "Challenger" expedition, and with which, it seems, large areas of the ocean s bed are thickly covered. The writer found in one of these, which seemed exceptionally rich in manganese, 20 12 per cent, of bin- oxide of manganese (fully oxidized), 4 of oxide of nickel, 25 of cobalt, and 27 of copper, a total of 21 04 per cent, of the psilomelanic part, not reckoning the CaO, MgO, &c., belonging to it. All the manganese ores named are available for the manufacture of chlorine, and indeed are so used, as components of what goes in the arts as " man ganese." The industrial value of a " manganese " depends, of course, on its actual or virtual percentage of binoxide. A convenient method for its determination was worked out by Fresenius and Will, on the basis of a reaction long before discovered by Turner. When MnO in brought in contact with aqueous sulphuric and oxalic acids, it is reduced to MnO (-salt) with formation of carbonic acid ; thus : MnO., + C 2 4 H 2 + H 2 S0 4 = 2H 2 + MnOS0 3 + 2C0 2 . It is easy so to arrange matters that all the C0 2 leaves the apparatus and nothing else, so that the weight of C0 2 formed identifies itself with the loss of weight suffered by the co-reagents ; and obviously every one gramme of C0 2 formed indicates ^ CQ 2 = II = 9986 gramme of real Mn0 2 . A determination of the free water (loss of weight suffered by the powdered ore at 120 C.) must accompany the assay to enable one to compare two analyses made at different times. For the making of manganese preparations, high class, pyrolusite is the most convenient raw material. Metallic manganese may be prepared by intimately mixing it with lamp-black and heating the mixture to whiteness in a blast furnace. But the regulus thus obtained contains a large percentage of combined carbon. A purer metal was obtained by Deville, who started with perfectly pure " red oxide, " Mn 3 4 , and heated it along with a proportion of sugar-charcoal insufficient for complete reduction in a double crucible made of quicklime. The unreduced oxide (MnO) and part of the lime fuse together into a violet slag, from which the regulus is easily

separated. Brunner s manganese (obtained by the reduc-