Eisen, 1893, 13, p. 559), by conversion of manganous oxide into
the sulphate obtained the value 54.883, and of the sulphate into
sulphide the value 54.876 (H = 1), and finally G. P. Baxter and
Hines (Jour. Amer. Chem. Soc., 1906, 28, p. 1360), by analyses of
the chloride and bromide, obtained 54.96 (O = 16).
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MANGANITE, a mineral consisting of hydrated manganese sesquioxide, Mn2O3·H2O, crystallizing in the orthorhombic system and isomorphous with diaspore and göthite. Crystals are prismatic and deeply striated parallel to their length; they are often grouped together in bundles. The colour is dark steel-grey to iron-black, and the lustre brilliant and submetallic: the streak is dark reddish-brown. The hardness is 4, and the specific gravity 4.3. There is a perfect cleavage parallel to the brachypinacoid, and less perfect cleavage parallel to the prism faces m. Twinned crystals are not infrequent. The mineral contains 89.7% of manganese sesquioxide; it dissolves in hydrochloric acid with evolution of chlorine. The best crystallized specimens are those from Ilfeld in the Harz, where the mineral occurs with calcite and barytes in veins traversing porphyry. Crystals have also been found at Ilmenau in Thuringia, Neukirch near Schlettstadt in Alsace (“newkirkite”), Granam near Towie in Aberdeenshire, Upton Pyne near Exeter and Negaunee in Michigan. As an ore of manganese it is much less abundant than pyrolusite or psilomelane. The name manganite was given by W. Haidinger in 1827: French authors adopt F. S. Beudant’s name “acerdèse,” (Gr. ἀκερδής, unprofitable) because the mineral is of little value for bleaching purposes as compared with pyrolusite. (L. J. S.)
MANGBETTU (Monbuttu), a negroid people of Central Africa
living to the south of the Niam-Niam in the Welle district of
Belgian Congo. They number about a million. Their country
is a table-land at an altitude of 2500 to 2800 ft. Despite its
abundant animal life, luxuriant vegetation and rich crops of
plantain and oil-palm, the Mangbettu have been some of the most
inveterate cannibals in Africa; but since the Congo State established
posts in the country (c. 1895) considerable efforts have
been made to stamp out cannibalism. Physically the Mangbettu
differ greatly from their negro neighbours. They are not so
black and their faces are less negroid, many having quite aquiline
noses. The beard, too, is fuller than in most negroes. They
appear to have imposed their language and customs on the
surrounding tribes, the Mundu, Abisanga, &c. Once a considerable
power, they have practically disappeared as far as the
original stock is concerned; their language and culture, however,
remain, maintained by their subjects, with whom they have to a
large extent intermixed. The men wear bark cloth, the art of
weaving being unknown, the women a simple loin cloth, often
not that. Both sexes paint the body in elaborate designs. As
potters, sculptors, boatbuilders and masons the Mangbettu
have had few rivals in Africa. Their huts, with pointed roofs,
were not only larger and better built, but were cleaner than those
of their neighbours, and some of their more important buildings
were of great size and exhibited some skill in architecture.
See G. A. Schweinfurth, Heart of Africa (1874); W. Junker, Travels in Africa (1890); G. Casati, Ten Years in Equatoria (1891).
MANGEL-WURZEL, or field-beet, a variety of the common
beet, known botanically as Beta vulgaris, var. macrorhiza. The
name is German and means literally “root of scarcity.” R. C. A.
Prior (Popular Names of British Plants) says it was originally
mangold, a word of doubtful meaning. The so-called root consists
of the much thickened primary root together with the
“hypocotyl,” i.e. the original stem between the root and the
seed-leaves. A transverse section of the root shows a similar
structure to the beet, namely a series of concentric rings of
firmer “woody” tissue alternating with rings of soft thin-walled
parenchymatous “bast-tissue” which often has a crimson or
yellowish tint. The root is a store of carbohydrate food-stuff
in the form of sugar, which is formed in the first year of growth
when the stem remains short and bears a rosette of large leaves.
If the plant be allowed to remain in the ground till the following
year strong leafy angular aerial stems are developed, 3 ft. or
more in height, which branch and bear the inflorescences. The
flowers are arranged in dense sessile clusters subtended by a
small bract, and resemble those of the true beet. The so-called
seeds are clusters of spurious fruits. After fertilization the
fleshy receptacle and the base of the perianth of each flower
enlarge and the flowers in a cluster become united; the fleshy
parts with the ovaries, each of which contains one seed, become
hard and woody. Hence several seeds are present in one “seed”
of commerce, which necessitates the careful thinning of a young
crop, as several seedlings may spring from one “seed.”
This plant is very susceptible of injury from frost, and hence in the short summer of Scotland it can neither be sown so early nor left in the ground so late as would be requisite for its mature growth. But it is peculiarly adapted for those southern parts of England where the climate is too hot and dry for the successful cultivation of the turnip. In feeding quality it rivals the swede; it is much relished by livestock—pigs especially doing remarkably well upon it; and it keeps in good condition till midsummer if required. The valuable constituent of mangel is dry matter which averages about 12% as against 11% in swedes. Of this two-thirds may be sugar, which only develops fully during storage. Indeed, it is only after it has been some months in the store heap that mangel becomes a palatable and safe food for cattle. It is, moreover, exempt from the attacks of the turnip beetle. On all these accounts, therefore, it is peculiarly valuable in those parts of Great Britain where the summer is usually hot and dry.
Up to the act of depositing the seed, the processes of preparation for mangel are similar to those described for the turnip; winter dunging being even more appropriate for the former than for the latter. The common drilling machines are easily fitted for sowing its large rough seeds, which should be sown from the beginning of April to the middle of May and may be deposited either on ridges or on the flat. The after culture is like that of the turnip. The plants are thinned out at distances of not less than 15 in. apart. Transplanting can be used for filling up of gaps with more certainty of success than in the case of swedes, but it is much more economical to avoid such gaps by sowing a little swede seed along with the mangel. Several varieties of the plant are cultivated—those in best repute being the long red, the yellow globe and the tankard, intermediate in shape. This crop requires a heavier dressing of manure than the turnip to grow it in perfection, and is much benefited by having salt mixed with the manure at the rate of 2 or 3 cwt. per acre. Nitrogenous manures are of more marked value than phosphatic manures. The crop requires to be secured in store heaps as early in autumn as possible, as it is easily injured by frost.
MANGLE. (1) A machine for pressing and smoothing clothes after washing (see Laundry). The word was adopted from the Dutch; mangel-stok means a rolling pin, and linnen mangelen, to press linen by rolling; similarly in O. Ital. mangano meant, according to Florio, “a presse to press buckrom,” &c. The origin of the word is to be found in the medieval Latin name, manganum, mangonus or mangana, for an engine of war, the “mangonel,” for hurling stones and other missiles (see Catapult). The Latin word was adapted from the Greek μάγγανον, a trick or device, cognate with μηχανή, a machine. (2) To cut in pieces, to damage or disfigure; to mutilate. This word is of obscure origin. According to the New English Dictionary it presents an Anglo-French mahangler, a form of mahaigner from which the English “maim” is derived, cf. the old form “mayhem,” surviving in legal phraseology. Skeat connects the word with the Latin mancus, maimed, with which “maim” is not cognate.
MANG LÖN, a state in the northern Shan states of Burma. It is the chief state of the Wa or Vü tribes, some of whom are head-hunters, and Mang Lön is the only one which as yet has direct relations with the British government. Estimated area, 3000 sq. m.; estimated population, 40,000. The state extends from about 21° 30′ to 23° N., or for 100 m. along the river
