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MICAH , in the See also:Bible, a See also:man of the See also:- HILL
- HILL (0. Eng. hyll; cf. Low Ger. hull, Mid. Dutch hul, allied to Lat. celsus, high, collis, hill, &c.)
- HILL, A
- HILL, AARON (1685-175o)
- HILL, AMBROSE POWELL
- HILL, DANIEL HARVEY (1821-1889)
- HILL, DAVID BENNETT (1843–1910)
- HILL, GEORGE BIRKBECK NORMAN (1835-1903)
- HILL, JAMES J
- HILL, JOHN (c. 1716-1775)
- HILL, MATTHEW DAVENPORT (1792-1872)
- HILL, OCTAVIA (1838– )
- HILL, ROWLAND (1744–1833)
- HILL, SIR ROWLAND (1795-1879)
hill-See also:country of See also:Ephraim whose See also:history enters into that of the See also:foundation of the Israelite See also:sanctuary at See also:Dan (See also:Judges xvii. seq.). He had stolen from his See also:mother eleven See also:hundred pieces of See also:silver (for the number cf. Judges xvi. 5), and when she uttered a curse upon the unknown thief he restored the See also:money and she consecrated it to Yahweh. A carved See also:image was made and set up in his private See also:temple together with an See also:ephod-idol and See also:teraphim (See also:objects used in See also:divination, cf. Gen. xxxi. 19, 30; Hos. iii. 4). He employed one of his sons to serve as See also:priest, but when a Levite from See also:Bethlehem in See also:Judah came along he gladly installed him as " See also:father and priest." When the tribe of Dan subsequently sought new territory and sent men to See also:search for a suitable See also:district they passed by Micah's See also:house, recognized the Levite and requested an See also:oracle from him. When, later, they migrated, they despoiled the sacred See also:place and carried off the gods and priest to their newly won See also:home at Laish.
See also:MICA-SCHIST,. in See also:petrology, a See also:rock composed essentially of mica and See also:quartz, and having a thin parallel-banded or foliated structure, with lamellae See also:rich in mica alternating with others which are principally quartz. They split readily along the micaceous films, and have smooth or slightly uneven surfaces covered with lustrous plates of See also:muscovite or See also:biotite; the quartzose lamellae are often visible only when the specimens are looked at edgewise. Mica-See also:schists are very See also:common in regions of Archean rocks accompanying gneisses, crystalline limestones and other schists. Some have a See also:flat banding yielding smooth slabs; others are crumpled or contorted with undulating foliation. Occasion-ally the quartz forms elliptical lenticles or " eyes." In some cases mica composes nearly the whole of the rock, in others quartz preponderates so that they approach quartz-schists and quartzites.
The mica may be muscovite or biotite; both are often See also:present, while paragonite and See also:green fuchsite or chrome-mica are not so common. In addition to quartz there may be a small amount of feldspar, usually See also:albite. A See also:great number of See also:accessory minerals are known in mica-schists, and when these are conspicuous or important they may be regarded as constituting See also:special varieties receiving distinctive names. See also:Garnet, in rounded red crystals, not uncommonly idiomorphic, is the most frequent. See also:- BROWN
- BROWN, CHARLES BROCKDEN (1771-181o)
- BROWN, FORD MADOX (1821-1893)
- BROWN, FRANCIS (1849- )
- BROWN, GEORGE (1818-188o)
- BROWN, HENRY KIRKE (1814-1886)
- BROWN, JACOB (1775–1828)
- BROWN, JOHN (1715–1766)
- BROWN, JOHN (1722-1787)
- BROWN, JOHN (1735–1788)
- BROWN, JOHN (1784–1858)
- BROWN, JOHN (1800-1859)
- BROWN, JOHN (1810—1882)
- BROWN, JOHN GEORGE (1831— )
- BROWN, ROBERT (1773-1858)
- BROWN, SAMUEL MORISON (1817—1856)
- BROWN, SIR GEORGE (1790-1865)
- BROWN, SIR JOHN (1816-1896)
- BROWN, SIR WILLIAM, BART
- BROWN, THOMAS (1663-1704)
- BROWN, THOMAS (1778-1820)
- BROWN, THOMAS EDWARD (1830-1897)
- BROWN, WILLIAM LAURENCE (1755–1830)
Brown See also:staurolite, pinkish See also:andalusite, and See also:grey or See also:blue kyanite occur in some kinds of mica-schist, separately or together. The See also:- WHITE
- WHITE, ANDREW DICKSON (1832– )
- WHITE, GILBERT (1720–1793)
- WHITE, HENRY KIRKE (1785-1806)
- WHITE, HUGH LAWSON (1773-1840)
- WHITE, JOSEPH BLANCO (1775-1841)
- WHITE, RICHARD GRANT (1822-1885)
- WHITE, ROBERT (1645-1704)
- WHITE, SIR GEORGE STUART (1835– )
- WHITE, SIR THOMAS (1492-1567)
- WHITE, SIR WILLIAM ARTHUR (1824--1891)
- WHITE, SIR WILLIAM HENRY (1845– )
- WHITE, THOMAS (1628-1698)
- WHITE, THOMAS (c. 1550-1624)
white mica-schist of the St Gothard contains kyanite and staurolite. See also:Graphite (or graphitoid) is also a very frequent ingredient of these rocks, giving them a leaden grey See also:colour and causing them to See also:soil the fingers when handled. In some mica-schists there is much See also:calcite (calc-mica-schists) ; and See also:hornblende, See also:scapolite and See also:augite are often seen in rocks of this sort. See also:Tourmaline occurs, sometimes in large See also:black prisms but more commonly in See also:minute crystals visible only in microscopic sections. See also:Rutile in tiny prisms, See also:ilmenite and hematite in black or brown scales, See also:zircon, See also:apatite, granules of See also:epidote or See also:zoisite See also:chlorite, chloritoid and See also:pyrites occur with more or less frequency in the rocks of this See also:group'
Mica-schists are in nearly all cases sedimentary rocks which have been recrystallized and have obtained a schistose structure during the See also:process. This can be proved by their chemical See also:composition, which is very much the same as that of See also:clays, shales and slates. In some districts it is possible to trace every gradation from a See also:slate (q.v.) to a mica-schist, the intermediate stages being represented by phyllites (q.v.) which consist of quartz, muscovite and chlorite, and are neither so crystalline nor so well foliated as the schists. In a few places, e.g. See also:Bergen in See also:Norway, fossils have been found in mica-schists. The association of quartzites and quartz-schists, graphiteschists and crystalline limestones with mica-schists in the See also:- FIELD (a word common to many West German languages, cf. Ger. Feld, Dutch veld, possibly cognate with O.E. f olde, the earth, and ultimately with root of the Gr. irAaror, broad)
- FIELD, CYRUS WEST (1819-1892)
- FIELD, DAVID DUDLEY (18o5-1894)
- FIELD, EUGENE (1850-1895)
- FIELD, FREDERICK (18o1—1885)
- FIELD, HENRY MARTYN (1822-1907)
- FIELD, JOHN (1782—1837)
- FIELD, MARSHALL (183 1906)
- FIELD, NATHAN (1587—1633)
- FIELD, STEPHEN JOHNSON (1816-1899)
- FIELD, WILLIAM VENTRIS FIELD, BARON (1813-1907)
field is explained by the fact that all these rocks are altered sediments, viz. sandstones, carbonaceous shales and limestones.
Under the See also:microscope the See also:appearance presented by mica-schists differs according to whether the rock is cut parallel to or across the planes of foliation. In the latter See also:case thin alternating bands composed of black or brown mica, and of quartz, See also:cross the field of view (see PETROLOGY, See also:Plate 4, fig. 8). The mica scales have their cleavages and their flat sides parallel; the quartz occurs in rounded, elliptical or irregular grains, with usually a small admixture of feldspar (albite, See also:oligoclase, See also:orthoclase) ; apatite and See also:iron oxides are rarely absent from these rocks. If garnet is present it may See also:form large well-shaped crystals containing innumerable enclosures of quartz, biotite and iron ores; in some cases the garnets are cracked as if they had been broken by the pressures to which the rock had been subjected. Often the garnets are surrounded by small " eyes " of quartz, and they may be embedded in green chlorite, which is probably a secondary or decomposition product. Some mica-schists are rich in iron oxides and pass into See also:haematite-schists (itabirites). When graphite occurs in mica-schists its crystals are small flat plates perfectly opaque even in the thinnest sections.
Like all metamorphic rocks, mica-schists are principally found in Archean areas; the great See also:majority of them are of pre-See also:Cambrian See also:age. There are, however, in the See also:Alps, Himalayas, &c., many rocks of this sort which are believed to be secondary or even See also:tertiary; the See also:evidence for this is not in all cases satisfactory, as of course the fossils, which if preserved would be sufficient to prove it, are nearly always destroyed by the See also:metamorphism. Mica-schists are rarely of economic value, being too fissile for See also:building-stones and too brittle for roofing-slates. They are of wide-spread See also:distribution in the Scottish See also:Highlands, Norway and See also:Sweden, Bohemia, See also:Saxony, See also:Brittany, the Alps, many parts of See also:North See also:America, &c. , (J. S.
End of Article: MICAH
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