664 



MANGANESE MANIIEIM. 



occurring crystallized in octal ledrons, with a square 

 lse, whose pyramids are inclined to each other, at 

 an angle of 117 30'. Fracture uneven; lustre im- 

 perfect metallic; colour brownish-black; streak dark- 

 mlilish or chestnut-brown; opaque; hardness equal 

 to that of apatite; specific gravity, 4-12. It also 

 occurs massive, possessed of a granular composition. 

 It is probable that the variety from Piedmont, ana- 

 lyzed by Berzelius, belonged to this species; if so, 

 its composition would be, oxide of manganese, 75'80; 

 silica, 13-17; oxide of iron, 4-14; and alumine, 2-80. 

 In the oxidating heat of the blow-pipe, it yields a 

 fine amethyst-coloured glass. It is soluble in heated 

 sulphuric acid. It lias been found in veins, in por- 

 phyry, along with other ores of manganese, at 

 Oehrenstock, near Ilmenau in Thuringia, and at 

 Ihlefield in the Hartz. 



3. Compact manganese ore, or uncleavuble man- 

 ganese ore, occurs in renifonn, botryoidal, and fruti- 

 cose shapes, having a columnar or granular composi- 

 tion, sometimes impalpable. Fracture flat conchoidal, 

 or even; lustre imperfect metallic; colour bluish- 

 black, passing into dark steel-gray; streak brownish- 

 black; shining; opaque; brittle; hardness nearly 

 equal to that of feldspar; specific gravity, 4-14. It 

 occurs sometimes accompanied by haematite, but 

 generally along with other ores of manganese, in 

 veins, in the older rocks. It is found at numerous 

 places in Europe, and in the United States. 



4. Manganese blende, or sulphuret of manganese, 

 is one of the rarest ores of this metal, and has hitherto 

 only been found at Nagyag in Transylvania, and in 

 Cornwall. It is rarely crystallized, generally occur- 

 ring irassive, in distinct concretions. Colour iron- 

 black; lustre imperfect metallic; streak dark green; 

 opaque; rather sectile; hardness but little superior to 

 that of calcareous spar; specific gravity, 4-014. It 

 consists of protoxide of manganese, 85-00, and sul- 

 phur, 15-00. Before the blow-pipe, it is melted 

 witli difficulty. If reduced to powder, and thrown 

 into nitric, muriatic, or dilute sulphuric acid, it emits 

 sulphureted hydrogen, and is dissolved. 



5. Phosphate of Manganese occurs massive, with 

 a cleavage in three directions, perpendicular to each 

 other, one of which is more distinct than the rest. 

 Fracture small conchoidal; lustre resinous; colour 

 blackish-brown ; streak yellowish or reddish-grey ; 

 opaque ; brittle ; hardness above that of apatite ; 

 specific gravity, 3-43. Before the blow-pipe, it melts 

 easily into a black scoria; is readily dissolved in nitric 

 acid, without effervescence, and consists of oxide of 

 iron, 3 1 '00; oxide of manganese, 42-00; and phos- 

 phoric acid, 27 '00. It has hitherto been found only 

 at Limoges in France, and at Washington in Con- 

 necticut. 



6. Carbonate of Manganese is found crystallized in 

 rhomboids of 106 51', and massive. Fracture un- 

 even, imperfectly conchoidal; lustre vitreous, inclining 

 to pearly; colour various shades of rose-red, partly 

 inclining to brown ; brittle ; hardness but little above 

 that of calcareous spar ; specific gravity, 3'59 ; the 

 massive varieties present globular and botryoidal 

 shapes; composition granular, sometimes small, and 

 even impalpable ; it consists of oxide of manganese, 

 54-60; carbonic acid, 33'75; oxide of iron, 1-87; 

 silica, 4-37; lime, 2-50. It effervesces rather briskly 

 in nitric acid ; before the blow-pipe, its colour is 

 changed into grey, brown, and black, and it decrepi- 

 tates strongly, but is infusible without addition. It 

 is found in the Saxon mines in the neighbourhood of 

 Friberg; also at Nagyag in Transylvania. For an 

 account of the red and reddish-brown silicious ores 

 ot manganese, see Silicate of Manganese. 



MANGEL-WURZEL; a kind of beet, which does 

 not afford fodder of as good quality, nor in such 



abundance, as was supposed at the time of its intro- 

 duction; but it is valuable from its size and hardy 

 nature. The leaves may be eaten as a substitute for 

 spinach, ami continue in season long after that plant 

 lias withered. In some parts of Germany, the far- 

 mers prefer it, for their cattle, to most vegetables; 

 and, besides, it can be obtained at the latter part of 

 the season, when green fodder is much wanted. 



MANGO; a celebrated fruit, now produced in 

 most of the tropical parts of the globe. It is a native 

 of India, and was introduced into Jamaica in the 

 year 1782. The taste is delicious, slightly acid, and 

 yields only to the mangosteen. The tree is allied to 

 the sumach, and belongs to the natural order terebin- 

 thacece. It attains the height of thirty or forty feet, 

 has a rapid growth, and is very productive. The 

 leaves are simple, alternate, lanceolate, coriaceous, 

 smooth, and entire. The flowers are inconspicuous, 

 reddish, and disposed in large terminal panicles. 

 The fruit is kidney-shaped, subject, however, to a 

 good deal of variation in size, form, and colour, and 

 contains a large, flattened stone. More than eighty 

 varieties of mango are cultivated, some of which are 

 very beautiful, and diffuse a delightful perfume. 



MANGOSTEEN. This far-famed fruit is the 

 product of a middling-sized and beautiful tree, the 

 garcinia mangostana of botanists, and was originally 

 brought from the Molucca islands, but is now culti- 

 vated in many parts of the East Indies. The leaves 

 are large, opposite, smooth, coriaceous, and entire : 

 the flowers are terminal and solitary, and of a deep- 

 red colour: the fruit is shaped like, and about as 

 large as an orange, divided internally into several 

 cells, each containing a single seed. It belongs to 

 the guttiferee, a natural family, which is not found 

 beyond the tropics. It is, on all hands, admitted to 

 be the most delicious, as well as the most wholesome, 

 of all known fruits. We have not heard of its 

 introduction into any part of inter-tropical America, 

 although great pains have been taken to transport 

 thither so many of the productions of the East. 



MANGROVE (rhizophora) ; a genus of plants, 

 consisting of trees or shrubs, which grow in tropical 

 countries, along the borders of the sea, in places 

 which are liable to be overflowed by the salt water, 

 even as far as low water mark. Their branches are 

 long, hang down towards the earth, and, when they 

 have reached it, take root, and produce new trunks. 

 In this manner, immense and almost impenetrable 

 forests are formed, which are filled with vast numbers 

 of crabs, aquatic birds, moschettoes, and also oysters, 

 which attach themselves to the branches. The leaves 

 are simple, opposite, and entire. The seeds are re- 

 markable for throwing out roots, which vegetate 

 among the branches of the trees, while yet adhering 

 to the foot-stalk. The R. mangle is found in Florida, 

 nearly as far north as the 30th parallel of latitude. 

 This genus, and an allied one, form a natural family 

 by themselves. 



MANHEIM; a city of Baden, capital of the circle 

 of the Neckar, at the conflux of the Neckar with the 

 Rhine; thirty-four miles N. of Carlsruhe; Ion. 8 

 28' E.; lat. 49 29' N.; population, 21,500. In 160G, 

 it was chosen by the elector palatine for the site of 

 a town, being, before, a petty village, with a castle. 

 In 1719, it became the residence of the elector 

 of the Palatinate and his court, and so continued till 

 1777. In 1802, it was annexed to Baden. It con- 

 tains a very large palace, is the second residence of 

 the grand duke, and the seat of the supreme court of 

 appeal for the grand duchy. Manheim presents a 

 fine view from a distance. It is divided into four 

 quarters, and is of an oval form. It is built with the 

 greatest regularity; the streets are wide, straight, 

 well paved, the houses uniform and neat, and the 



