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Magneto. work on this reciprocal principle, and a description of them will best show how it is turned to account. Ladd was the first to construct a machine on Wheatstone and Siemens's principle. In the armature there are two unequal coils, the larger for furnishing the external current, the smaller for exciting the electro-magnet. These two coils revolve together, the one at right angles to the other, in the same magnetcylinder. In large machines he uses two magnet-cylinders, one at each end of the electro-magnet; or rather, he uses two electro-magnets, and the two armatures complete the magnetic circuit. Ferguson of Edinburgh alters Ladd's arrangement in using only one piece of iron for the armature of the machine with two grooves cut in it, a larger one for the coil giving the external current, and a smaller one for the exciting current. This offers the advantage that the heating of the solid iron of the armature by repeated magnetism is lessened by being transformed into an electric current. The electro-magnet is thus fed by a current obtained not by an additional expenditure of energy, but by the utilization of force that would be otherwise converted into useless or even hurtful heat.

The great drawback of all the forms of the machine just described is the enormous velocity at which they rotate-some 2,000 or more revolutions in the minute. At this speed a machine soon wears itself out. Another disadvantage is the heating of the armatures in Wilde and Ladd's machine. Ferguson's has never been tried on a large scale. It is found necessary to keep the armatures cool by a flow of cold water. This heat, however removed, is manifestly a mere squandering of the energy of motion, and a loss to the current given off. A third objection is the loss that always takes place when the sidesprings change from the one ring to the other, sparks more or less bright accompanying the change. For the electric light, however, the alternate currents are used, and this source of loss is not experienced. These defects are removed in the latest form of the electro-magnetic machine by Gramme of Paris. In it, instead of a solid armature of iron, a ring is employed on which a great number of bobbins of wire are set. Fig. 4 is intended to explain the rudimentary prin

ciple of it. The ends of the wires of two contiguous bobbins are soldered to strips of metal called sectors. These are shown as radii in the figure. In the machine itself they are first brought down radially, then turned at right angles so as to be parallel to the axis of the machine. They are very numerous (though few in the figure), and being separated from each other by sheets of silk, form a compact whole. Metallic brushes, B, B, rub on the end face of the sectors, and form the poles of the revolving armature. The principle of action may be thus understood: Suppose we first ascertain what takes place in the coil of one bobbin as it revolves in the presence of the magnetic poles, P, N. If we start from the equatorial line, E E', and go by successive impulses, we find that, when the bobbin

Fig. 4.

MOAK

is joined with a galvanometer, the current induced is always in one direction until we come again to the equatorial line; but when we pass this, the current is reversed on the other side. This is much the same as what is found in the Siemens armature. But there is this difference here: The armature wire with the sectors is continuous from end to end. On each side of the equatorial line we have two equal and opposite elec tric forces or batteries, and these, if left alone, would neutralize each other. But if, in the equatorial line, we introduce brushes to act as poles, we have, as it were, two gal vanic batteries joined up, as it is called, in quantity, with both positive poles together and also both negative. The brushes embrace several sectors at once, so there is no spark when they leave any particular sector, contact being established with the others. The conditions of the machine never alter, and hence the current is perfectly steady, and the sectors being always of the same sign at the points where the brushes rub, the current is always in the same direction. Siemens and Wheatstone's principle is employed in Gramme machines. There are two fixed electro-magnets, and two armatures on the same spindle; one electro-magnet and one armature being set apart for exciting both electro-magnets, and the other armature and electro-magnet for sending out the external current. Astonishing as were the effects produced by Wilde's machine, those obtained from Gramme's seem quite to eclipse them. In comparing two magneto. electric machines, we must take into account the kind of wire used for the revolving armature. For tension purposes, a thin and long wire gives the best results; for quantity or heating purposes, a short and thick wire does best. To compare a tension with a quantity armature, the same test even in the same machine would give most contra dictory results. But comparing, so far as possible, machines intended for the same purpose, Gramme seems to have the advantage of all others. In the first place, the U. K. IX.-24

Magpie.

speed of revolution seldom exceeds 800 revolutions per minute; 300 is sufficient for most purposes. A Gramme machine driven by the hand will melt 10 in. of an iron wire of an inch in diameter, a feat not accomplished by any other arrangement. The electric light got by a 3-horse-power engine working a machine a ton in weight is equal to upwards of 8,000 sperm candles. A signal-light of this kind has been constructed for the house of lords, under the superintendence of the eminent engineer Conrad W. Cooke, who has rendered no small service in perfecting the machine. The carbons consumed last for four hours, and when burned out are instantaneously replaced. A Gramme machine adapted for electro-plating, and worked by a 1-horse-power engine, deposits nearly 27 oz. of silver per hour, an achievement far transcending the similar performance of other machines. Among the heating wonders of the Gramme machine we are told of a file half an inch in diameter being burnt up in 5 minutes, of 15 ft. of No. 18 platinum wire being brought to a glowing heat, and of 8 ft. of iron wire .051 inch in diameter being fused.

MAGNIFICAT, a musical composition in the evening service of the Roman Catholic church, and also of the Lutheran and English churches. The words are taken from Luke i. 46-55, containing the “ song of the Virgin Mary," which, in the Vulgate, begins with Magnificat. In the Roman Catholic church, the Magnificat is a grand hymn, powerful in melody and harmony, mixed with pompous fugues, and with full instrumentation. In modern time there have been few attempts in the Roman Catholic service to supersede the older music of the Magnificat (by Palestrina); but in the service of the church of England, where the music is of a less elevated character, new compositions are frequently written for the Magnificat, by composers strictly of the English school,

MAGNIFYING-GLASS. See MICROSCOPE, ante.

MAGNIN, CHARLES, 1793-1862; b. Paris; received a superior education, and at the age of 20 became an assistant in the imperial library, and in 1832 a director. He wrote for the Paris press, theatrical criticism, essays, and sketches, and attracted the favorable notice of leading French writers. He also delivered lectures at the Sorbonne on the origin of the modern stage, and gained a sufficient reputation as a man of learning to obtain a seat in the academy of inscriptions and belles-lettres. His published works include Causeries et Méditations Historiques et Littéraires; Les Origines du Théâtre Moderne; Le Théâtre des Hrosvitha; and Histoire des Marionettes.

MAGNOLIA, a genus of beautiful trees of the natural order magnoliacea, having a calyx of 3 sepals, a corolla of 6 to 12 petals, and carpels in spikes arranged in cones, and opening at the dorsal suture. They are natives chiefly of North America, the Himalaya mountains, China, and Japan. The flowers are large and solitary; the leaves large. The wood is in general soft, spongy, and of little value. M. grandiflora, sometimes called the BIG LAUREL, has white flowers sometimes a foot in diameter. It is a lofty and magnificent evergreen tree, conspicuous at a great distance, found in the lower districts from North Carolina to the gulf of Mexico. It succeeds well as an ornamental tree in the s. of England, but in Scotland requires a wall and some protection in winter. M. tripetala is found on the Alleghany mountains, and extends as far n. as lat. 43°. From the radiated manner in which its leaves are disposed at the extremities of the branches, it has received the name of UMBRELLA TREE. It has very large white flowers. It is one of the species most commonly cultivated in Britain, but in Scotland it requires a wall. M. acuminata inhabits the same districts, and is a lofty tree with greenish-yellow flowers. It endures the climate of Britain well, but its flowers are not so much admired as those of some of its congeners. M. glauca, a native of Pennsylvania, Virginia, and Carolina, is known by the names of WHITE BAY, BEAVERWOOD, and SWAMP SASSAFRAS. It is a tree or shrub of 15 to 20 ft. in height, with very beautiful and fragrant white flowers. The YULAN, or Chinese magnolia (M. yulan or conspicua), has been much cultivated in China for more than 1200 years, on account of its beautiful and fragrant white flowers, which it produces in great profusion. It is one of the finest ornamental trees we possess, and succeeds well in the s. of England, and against a wall in Scotland. It is a deciduous tree, and the flowers expand before the development of the leaves. M. excelsa, one of the finest species known, is a predominant tree in some parts of the Himalaya mountains, at an elevation of 7,000 or 8,000 ft., the mountains when it is in blossom appearing as sprinkled with snow. M. Campbellii, another native of the same region, produces great rose-colored flowers, and is described by Dr. Hooker as the most superb of the genus. Allied to the genus magnolia is Michelia, some of the species of which are amongst the most valuable timber trees of Nepaul, and very ornamental. The bark of some of them is used medicinally, and the fragrant flowers of a species called champac are the delight of the people of Hindustan. Manglietia is another closely allied genus, to which belong valuable timber trees of Nepaul and of the Indian islands. The natural order magnoliacea is closely allied to ranunculacea, differing chiefly in the arborescent habit, and in the large stipules which envelop the young leaves before they open, but soon fall off. The leaves are simple. Aromatic properties are prevalent. To this order belong the tulip tree, star anise, and winter's bark.

MAGNUS, HEINRICH GUSTAV, 1802–70; b. Berlin; educated at the university of Berlin, where he devoted himself to the study of natural science. He also studied chemistry with Berzelius at Stockholm. At the age of 26 he had already made important discoveries in chemistry, and in 1834 was made extraordinary, and in 1845, ordinary professor of physics and technology in the Berlin university. He made important experiments on the transmission of heat through gases, which were published in 1860.

MAGNUSSEN, FINN, a distinguished scholar and archæologist, was b. in 1781 at Skabholt, in Iceland, where his family, both on his mother's and father's side, had for many generations been distinguished for learning and integrity. In 1797 Magnussen entered the university of Copenhagen with a view of studying for the law; and although he so far fullfilled the original intention of his education as to practice this profession for some years in Iceland, his strong bent towards archæological pursuits led him, in 1812, to return to Copenhagen, where he devoted himself with much zeal to his favorite studies, under the direction of his distinguished countrymen, Thorkelin and Thorlacius. In 1815 he obtained a chair of literature in the university; and in 1819, at the solicitation of the academy of fine arts, he gave a course of lectures on ancient northern literature and mythology. From this, or even an earlier period, to the close of his life, Magnussen devoted himself to the elucidation of these subjects with a success that was generally commensurate with the great ability and acute learning which he brought to bear upon it, although in some few instances his zeal led him to adopt too hasty conclusions. Among his earliest and most noteworthy works are his papers on the aboriginal home and earliest migrations of the Caucasian races (1818); his contributions to northern archæology (1820); the indices, glossaries, and lexicon which he compiled for the elucidation of the 2d and 3d of the Arne-Magnussen editions of the Eddas (1818 and 1823); his comprehensive translation of the Elder Edda (Aldre Edda, oversat og forklaret, Kopen. 1824); and his exposition of the same work (Edda læren og dens Opfindelse, Kop. 1824). Among his later works, his Runamo og Runerne (Kop. 1841) has given rise to much angry discussion; and although many of his interpretations of assumed runes have been proved to be utterly untenable, the learning and acumen which he brought to bear on the subject of runes generally, have thrown great light on this branch of archæology, both in regard to North American and ancient northern remains. In conjunction with Rafn, Magnussen elucidated the history and antiquities of Greenland in an able work (Grönland's Historiske Mindesmerker, Kop. 1838-42); and he subsequently prosecuted a similar course of inquiry in regard to Russia in Antiquités Russes (Cop. 1850-52). In addition to these works, Magnussen annotated nearly all the most important remains of old northern literature, as the Heimskringla, Hakonarmal, Laxdæla-Saga, etc.; and besides numerous monographs on arcnæological and historic subjects of interest, made many valuable contributions te current Icelandic literature. During his latter years, Magnussen sat in the Danish landthing as deputy for Iceland and the Faroe isles, in which capacity he gave evidence of considerable political knowledge and patriotic zeal. At his death, in 1847, he held the office of Geheimarchivar in the royal chamber of archives.

MAGO, a common Carthaginian name; no less than 14 different persons bearing it occur in history; of whom the most distinguished is Mago, the son of Hamilcar Barca, and a younger brother of Hannibal (q.v.) and Hasdrubal.

MAGOF FIN, an e. co. of Kentucky, drained by the Licking river, and bounded on the e. by mountain ranges. The surface varies in character, being fertile in parts; 600 sq.m.; pop. '80, 6,943. The productions are not abundant; wheat, Indian corn, wool, potatoes, oats, and butter, are the most important. Co. seat, Salyersville.

MAGOON', ELISHA L., D.D., b. N. H 1810; at first a bricklayer, but in 1840 ordained to the ministry of a Baptist church, and settled at Richmond, Va. After a tour in Europe, and pastorates at New York and Albany, he removed in 1860 to Philadelphia, where he remains. He has published Orators of the American Revolution, 1848; Living Orators of America, 1849; Republican Christianity, 1849; and Westward Empire, 1856. He has shown broad literary taste and culture.

MAGPIE, or PIE (Pica), a genus of birds of the family Corvida (q.v.), differing from the true crows chiefly in the long and graduated tail. They are also of smaller size and brighter colors, the most prevalent color being blue with bars of black and white. The only British species is the COMMON MAGPIE (P. caudata), the Kitta of the Greeks, and Pica of the Romans; a common bird in Britain, and almost all parts of Europe, and too well known to require particular description; its bright but not finely mingled colorsblack, white, and blue-making it always conspicuous, and its dissonant, harsh cry equally attracting attention. The magpie is generally to be seen in pairs throughout the year. It builds its nest in high trees; the outside being formed of thorny sticks strongly interwoven, the inside plastered with earth and lined with fibers and dry grass; the top a dome, and one aperture left on the side for the parent bird. The magpie is shy and vigilant in an extreme degree, notable for cunning, both in eluding enemies, and in seeking its own food, as to which it may be said that nothing comes amiss to it, grain being not unacceptable, but eggs or carrion preferable. In Britain, it is persecuted by gamekeepers; in Norway, it is encouraged in the neighborhood of human habitations, and

Mahan.

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consequently often makes its nest under the eaves of churches and other buildings. magpie is easily tamed, becomes impudently familiar, and learns to articulate a few words. Both in a wild and tame state, it has a propensity to seize and carry off bright or glittering articles. It abounds in most parts of Europe and the north of Asia, and in the northern parts of America, but is rare in the parts of America near the Atlantic.The other species are mostly natives of the eastern parts of Asia.

MAGRUDER, JOHN BANKHEAD, 1810-71; b. Va.; graduated at the military academy In 1830, and was appointed second lieut. in the infantry. He was promoted first lieut. in 1835, and capt. in 1846. He served with distinction through the Mexican war, at the head of the light battery attached to the division of gen. Pillow. He was brevetted maj. after Cerro Gordo, and lieut. col. after Chapultepec, where he was wounded. He resigned from the army April 2, 1861, to enter the confederate service, in which he was made successively col., brig.gen., and maj.gen. He was at first attached to the army of Virginia, commanding at Yorktown till its evacuation in May, 1862, when he joined the campaign on the Chickahominy. In October of the same year he went to Texas to take command of the department of the west, embracing, besides Texas, Arizona and New Mexico. He remained in active service in Texas throughout the war, conducting a number of military operations, of which the most brilliant resulted in the abandonment of Galveston by the federal forces. After the war he lived for a time in Mexico, but afterwards settled in Texas.

MAGUIRE, JOHN FRANCIS, 1815-72, b. Ireland; a lawyer and journalist. He sat in parliament as member for Dungarvon from 1852 to 1865, and for Cork from 1865 till his death. He was mayor of Cork for several years, and owned and edited there the Cork Examiner. He was the author of The Industrial Movement in Ireland in 1852; Rome and its Ruler; The Irish in America; Life of Father Mathew, and The Next Generation. MAG'YAR. See HUNGARY.

MAHABHARATA (from the Sanskrit mahat-changed to maha-great, and Bhárata) is the name of one of the two great epic poems of ancient India. For the other, see the article RAMAYAN'A. As its main story relates to the contest between two rival families, both descendants of a king, Bharata, the word Mahâbhârata probably implies "the great history of the descendants of Bharata;" for another explanation of the word, which connects it with bhara, weight, was obviously invented merely to convey an idea of the enormous extent of this poem. According to this explanation, it would mean the "very weighty (poem)," because, when weighed, it was found to be heavier than all the four Vedas together with their mystical writings." However devoid of grammatical value this popular account of the word Mahâbhârata may be, it does not exaggerate the bulk of this epos, which, in its present condition, consists of upwards of 100,000 verses, each containing 32 syllables; while, if a tradtition, reported in the introduction to the work itself, could be trusted, it was formerly known in other recensions of a still greater extent. In its actual shape, it is divided into 18 parvans or books, the Harivansa (q.v.) being considered as a supplementary part of it. That this huge composition was not the work of one single individual, but a production of successive ages, clearly results from the multifariousness of its contents, from the difference of style which characterizes its various parts, and even from the contradictions which disturb its harmony. Hindu tradition ascribes it to Vyása; but as Vyâsa means "the distributer or arranger;" and as the same individual is also the reputed compiler of the Vedas, Purânas, and several other works, it is obvious that no historical value can be assigned to this generic name. The contents of the Mahâbhârata may be distinguished into the leading story and the episodical matter connected with it. The former is probably founded on real events in the oldest history of India, though in the epic narrative it will be difficult to disentangle the reality from the fiction. The story comprises the contest of the celebrated families called the Kauravas and Pândavas, ending in the victory of the latter, and in the establishment of their rule over the northern part of India. Kuru, a descendant of Bharata, had two sons, Dhritarâshtra and Pându. The sons of the former, commonly called the Kauravas, were a hundred in number, the eldest of them being Duryodhana; those of Pându-the Pandavas were five, Yudhishthira, Bhima, Arjuna, and the twins Nakula and Sahadeva. Pându having resigned his throne, Dhritarashtra, though blind, assumed the government, and ultimately divided his kingdom between his sons and the sons of Pându. The former, however, coveting the territory allotted to the Pându princes, endeavored to get possession of it. A game of dice was the means by which they bound over their cousins to relinquish their kingdom, promising, however, to restore it to them if they passed twelve years in the forests, and a thirteenth year in such disguises as to escape detection. This promise was faithfully kept by the Pândavas; but the term of their banishment having expired, the Kuru princes refused to redeem their word. A war ensued, ending in the complete destruction of the Kauravas. These are the meager outlines of the leading story of the Mahâbhârata, where, as may be inferred, Duryodhana and his brothers are pictured as the type of all conceivable wickedness, and the Pându princes as paragons of virtue and heroism. That the latter are the incarnations of sundry deities-that the gods take an active part in the development of the plot, in short, that Hindu mythology is always interwoven with these stirring

events of semi-historical Hindu antiquities, requires no further remark to any one but slightly acquainted with Hindu poetry. It is necessary, however, to observe that out of the 100,000 verses which constitute the great epos, barely a fourth part is taken up by this narrative; all the rest is episodical. The matter thus, as it were, incidentally linked with the main story, may be distributed under three principal heads, passing over such minor additions as fables, genealogical lists, geographical enumerations, and the like. One category of such episodes comprises narratives relating to the ancient or mythical hystory of India, as, for instance, the episodes of Nala and Sakuntalâ; a second is more strictly mythological, comprising cosmogony and theogony; a third is didactic or dogmatic-it refers to law, religion, morals, and philosophy, as in the case of the celebrated Bhagavadgîtâ, and the principal portions of the 12th and 13th books. By means of this episodical matter, which at various periods, and often without regard to consistency, was superadded to the original structure of the work, the Mahabharata gradually became a collection of all that was needed to be known by an educated Hindu; in fact, it became the encyclopædia of India. "There is no narrative on earth," the Mahabharata says of itself, that is not founded on this epos. .. The twice-born, though knowing the four Vedas and their supplementary sciences, has no wisdom unless he knows this great epos. It is the great manual of all that is moral, useful, and agreeable." Yet it should be noticed that the Brahmanic authors of the great epos intended it especially as an encyclopædia for the Kshattriya or military caste; for it is chiefly the history, the interests, the religion, and the duties of the second caste which are taught in it, always, of course, with a view of establishing the superiority of the Brahmanic caste. Sectarian religion is for this reason not emphasized in the Mahâbhârata, though the later sectarian works (see PURANA) have largely drawn, for their purposes, on the mythological material afforded them by the great epic work. The text of the Mahabharata has been published in Calcutta in four quarto volumes (1834-39), to which is added a fifth volume, containing a table of contents. Two other editions are in the course of publication at Bombay The best researches on the Mahabharata are those of Lassen, in his Zeitschrift für die Kunde des Morgenlandes (1837, ff.), and in his Indische Alterthumskunde. A sort of analysis of the leading story of the Mahâbhârata (not of the episodes) is given in Eichhoff's Poésie Héroïque des Indiens (Paris, 1860), and by Prof. Monier Williams (Indian Epic Poetry, London, 1863). See also Talboys Wheeler's History of India (1867).

MAHADEVA (“the great god") is one of the usual names by which the Hindu god Si'va is called. (His consort, Durgâ, is similarly styled Mahadevi, ("the great goddess.") In Buddhistic history. Mahadeva, who lived 200 years after the death of the Buddha S'âkyamuni, or 343, is a renowned teacher who caused a schism in the Buddhistic church. His adversaries accuse him of every possible crime, but as he is ranked among the Arhats, his eminence cannot be matter of doubt. The school founded by him is called Púrvasaila. See W. Wassiljew, Der Buddhismus, etc. (St. Petersburg, 1860).

MAHAKÂS'YAPA, one of the most renowned disciples of the Buddha S'âkyamuni. He arranged metaphysically the portion of the sacred writings of the Buddhists called Abhidharma; and tradition ascribes to him also the origin of the Sthavira division of the Vaibhashika school of Buddhistic philosophy. Many legends are connected with his life. See E. Burnouf, Introduction à l'Histoire du Buddhisme Indien (Paris, 1844), and his posthumous work, Le Lotus de la Bonne Loi (Paris, 1852).

MAHAN', ASA, D.D., b. in Vernon, N. Y., in 1799; graduated at Hamilton college in 1824, and at Andover theological seminary in 1827; in 1829 became pastor of a Presbyterian church in Pittsford, N. Y., and of a church of the same denomination in Cincinnati in 1831; became president and professor of philosophy at Oberlin in 1835; was president of Cleveland university from 1850-56; pastor of a Congregational church in Jackson, Mich., from 1856-58, and of another at Adrian from 1858-61; and president of Adrian college from 1861-71. His principal works are, The Scripture Doctrine of Christian Perfection; the Science of Intellectual Philosophy; the Doctrine of the Will; the Science of Moral Philosophy; the Science of Logic; and Modern Mysteries Explained and Refutedthe latter directed against spiritualism. He has written also a work of some size in the department of military criticism.

MAHAN, DENNIS HART, LL.D., 1802-71; b. N.Y.; educated at West Point, and appointed to the army in the engineer corps. In 1825 he was made assistant professor of mathematics at the academy; and in 1832, after four years of study abroad, professor of military engineering, and remained at West Point in that capacity till his death, which occurred by suicide in a fit of temporary insanity. He stood high in his profession, and he wrote a number of text books on civil and military engineering, which came into general use in schools and colleges in the United States. His Treatise on Field Fortifications appeared in 1836, and was supplemented in 1865, by Military Mining and Siege Operations, the two constituting parts I. and II. respectively, of An Elementary Course of Military Engineering. He also published An Elementary Course of Civil Engineering in 1837, which he rewrote and revised in 1868; Advanced Guard, Outpost, and Detachment Service of Troops, 1847; Elementary Treatise on Industrial Drawing, 1853; Descriptive Geometry, 1864; and an edition of Moseley's Mechanical Principles of Engineering and

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