See also:

• PORPHYRY (IlopcPisptos) (A.D. 233-c. 304)

PORPHYRY (IlopcPisptos) (A.D. 233-c. 304)  , See also:

• GREEK
• GREEK, ETRUSCAN AND

Greek See also:

• SCHOLAR, SCHOLARSHIP

scholar, historian, and Neoplatonist, was See also:

• BORN, IGNAZ, EDLER VON (1742–1791)

born at See also:

• TYRE (Phoen. and Hebr. =" rock," Assyr. S'urru, Egypt. Dara, Early Lat. Sarra)

Tyre, or Batanaea in See also:

• SYRIA

Syria . He studied See also:

• GRAMMAR (from Lat. grammatica, sc. ars; Gr. ypaµ)

grammar and See also:

• RHETORIC (Gr. psroperctj TEXvq, the art of the orator)

rhetoric under See also:

• CASSIUS
• CASSIUS, AVIDIUS (d. A.D. 175)
• CASSIUS, GAIUS

Cassius See also:

• LONGINUS, CASSIUS (c. A.D. 213-273)

Longinus (q.v.) . His See also:

• ORIGINAL

original name was Malchus (See also:

• KING
• KING (O. Eng. cyning, abbreviated into cyng, cing; cf. O. H. G. chun- kuning, chun- kunig, M.H.G. kiinic, kiinec, kiinc, Mod. Ger. Konig, O. Norse konungr, kongr, Swed. konung, kung)
• KING [OF OCKHAM], PETER KING, 1ST BARON (1669-1734)
• KING, CHARLES WILLIAM (1818-1888)
• KING, CLARENCE (1842–1901)
• KING, EDWARD (1612–1637)
• KING, EDWARD (1829–1910)
• KING, HENRY (1591-1669)
• KING, RUFUS (1755–1827)
• KING, THOMAS (1730–1805)
• KING, WILLIAM (1650-1729)
• KING, WILLIAM (1663–1712)

king), which was changed by his See also:

• TUTOR (Lat. tutor, guardian, tueri, to watch over, protect)

tutor into Porphyrius (clad in See also:

• PURPLE

purple), a jesting allusion to the See also:

• COLOUR (Lat. color, connected with celare, to hide, the root meaning, therefore, being that of a covering)

colour of the imperial See also:

• ROBES (Fr. robe, Late Lat. roba, raupa, meaning (1)

robes (cf. porphyrogenitus, born in the purple) . In 262 he went to See also:

• ROME
• ROME (Roma)

Rome attracted by the reputation of See also:

• PLOTINUS (A.D. 204-270)

Plotinus, and for six years. devoted himself to the study of See also:

• NEOPLATONISM

Neoplatonism . Having injured his See also:

• HEALTH

health by overwork, he went to live in See also:

• SICILY (Ital. Sicilia)

Sicily for five years . On his return to Rome, he lectured on See also:

• PHILOSOPHY (Gr. gthos, fond of, and vo4 (a, wisdom)

philosophy and endeavoured to render the obscure doctrines of Plotinus (who had died in the meantime) intelligible to the See also:

• ORDINARY (med. Lat. ordinarius, Fr. ordinaire)

ordinary understanding . His most distinguished See also:

• PUPIL (Lat. pupillus, orphan, minor, dim. of pupus, boy, allied to puer, from root pm- or peu-, to beget, cf. "pupa," Lat. for " doll," the name given to the stage intervening between the larval and imaginal stages in certain insects)

pupil was See also:

• IAMBLICHUS
• IAMBLICHUS (d. c. A.D. 330)

Iamblichus . When advanced in years he married Marcella, a widow with seven See also:

• CHILDREN, LAW RELATING TO

children and an enthusiastic student of philosophy . Nothing more is known of his See also:

• LIFE

life, and the date of his See also:

• DEATH

death is uncertain . Of his numerous See also:

• WORKS

works on a See also:

• GREAT

great variety of subjects the following are extant: Life of Plotinus and an exposition of his teaching in the 'Ad,oppat trpbs ra vomra (Sententiae ad intelligioitia ducentes, See also:

• AIDS

Aids to the study of the Intelligibles) . The Life of See also:

• PYTHAGORAS
• PYTHAGORAS (6th century B.C.)

Pythagoras, which is incomplete, probably formed See also:

• PART

part of a larger See also:

• HISTORY

history of philosophy (OtXOaocos Laropia, in four books) down to See also:

• PLATO

Plato . His See also:

• WORK

work on See also:

• ARISTOTLE
• ARISTOTLE (384-322 B.C.)

Aristotle is represented by the Introduction (etaay eyb) to and Commentary (i,il ynacs, in the See also:

• FORM (Lat. forma)

form of questions and answers) on the Categories .

The first, translated into Latin by See also:

• BOETIUS (or BoETxlus), ANICIUS MANLIUS SEVERINUS (c. A.D. 480–524)

Boetius, was extensively used in the See also:

• MIDDLE

middle ages as a compendium of Aristotelian See also:

• LOGIC (Xoy1K7, sc. rixvrt, the art of reasoning)

logic; of the second only fragments have been preserved . His XponK6, a See also:

• CHRONOLOGICAL

chronological work, extended from the taking of See also:

• TROY
• TROY, JEAN FRANCOIS DE (1679–1752)

Troy down to A.D . 270; to it See also:

• EUSEBIUS
• EUSEBIUS (Gr. EuOi/3tos, from ebaegils, pious, cf. the Latin name Pius)
• EUSEBIUS [OF CAESAREA] (c. 260-c. 340)
• EUSEBIUS [OF EMESA] (d. c. "36o)

Eusebius is indebted for his See also:

• LIST (O.E. lisle, a Teutonic word, cf. Dut. lust, Ger. Leiste, adapted in Ital. lista and Fr. lisle)
• LIST, FRIEDRICH (1789-1846)

list of the Macedonian See also:

• KINGS, FIRST AND SECOND BOOKS OF

kings . The See also:

• TREATISE

treatise ¢uXbxoyos iaropta is called an tucpbaais (lecture) by Eusebius, who in his Praeparatio eveingelica (x . 3) has preserved a considerable See also:

• EXTRACT (from Lat. extrahere, to draw out)

extract from it, treating of See also:

• PLAGIARISM

plagiarism amongst the ancients . Other grammatical and See also:

• LITERARY

literary works are 'Opnpuua NT, ara (Quaestiones homericae); and De antro nymph-arum, in which the description in the Odyssey (xiii . 102—112) is explained as an See also:

• ALLEGORY (iXXos, other, and ayopeuav, to speak)

allegory of the universe . The Ilept airoxits ep'l+bxwv (De abstinentia), on See also:

• ABSTINENCE (from Lat. abstinere, to abstain)

abstinence from See also:

• ANIMAL
• ANIMAL (Lat. animalis, from anima, breath, soul)

animal See also:

• FOOD
• FOOD (like the verb " to feed," from a Teutonic root, whence O. Eng. foda; cf. " fodder "; connected with Gr. lrareicOae, to feed)

food, is especially valuable as having preserved numerous original statements of the old philosophers and the substance of See also:

• THEOPHRASTUS

Theophrastus's IIepi sbsr etas (On Piety) . It also contains a See also:

• LONG, GEORGE (1800-1879)
• LONG, JOHN DAVIS (1838– )

long fragment from the Cretans of See also:

• EURIPIDES (48o–4o6 B.C.)

Euripides . The IIpbs MapseXAav is an exhortation to his wife Marcella to practise virtue and self-See also:

• RESTRAINT (from " to restrain," Lat. restringere, to hold back, prevent)

restraint and to study philosophy . The See also:

• LETTER (through Fr. lettre from Lat. littera or litera, letter of the alphabet; the origin of the Latin word is obscure; it has probably no connexion with the root of linere, to smear, i.e. with wax, for an inscription with a stilus)

letter to the See also:

• EGYPTIAN

Egyptian See also:

• PRIEST (Ger. Priester, Fr. pretre)

priest Anebo, dealing with religious questions, was answered by a member of the school of Iamblichus, who called himself Abammon, in the De mysteriis . It is frequently referred to by Eusebius, See also:

• CYRIL (376-444)
• CYRIL (827-869)
• CYRIL (c. 315–386)

Cyril and See also:

• AUGUSTINE, SAINT (354-430)
• AUGUSTINE, SAINT (d. c.613)

Augustine .

Eusebius preserved fragments of the IIepi rits is Xoyiwv aaXoao';btas (De philosophia ex oraculis haurienda), in which he expressed his belief in the responses of the oracles of various gods as confirming his theosophical views . See also:

• PORPHYRY (IlopcPisptos) (A.D. 233-c. 304)

Porphyry is well known as a violent opponent of See also:

• CHRISTIANITY

Christianity and defender of Paganism; of his Kara Xpcarcavc;w (Adversus Christianos) in 15 books, perhaps the most important of all his works, only fragments remain . See also:

• COUNTER

Counter-See also:

• TREATISES

treatises were written by Eusebius of Caesarea, Apollinarius (or See also:

• APOLLINARIS
• APOLLINARIS, SULPICIUS

Apollinaris) of See also:

• LAODICEA
• LAODICEA, SYNOD OF

Laodicea, See also:

• METHODIUS (c. 825-885)

Methodius of See also:

• OLYMPUS

Olympus, and Macarius of See also:

• MAGNESIA

Magnesia, but all these are lost . Porphyry's view of the See also:

• BOOK

book of See also:

• DANIEL
• DANIEL (DANIL)
• DANIEL, BOOK
• DANIEL, GABRIEL (1649-1728)

Daniel, that it was the work of a writer in the See also:

• TIME (0. Eng. Lima, cf. Icel. timi, Swed. timme, hour, Dan. time; from the root also seen in " tide," properly the time of between the flow and ebb of the sea, cf. O. Eng. getidan, to happen, " even-tide," &c.; it is not directly related to Lat. tempus)
• TIME, MEASUREMENT OF
• TIME, STANDARD

time of See also:

• ANTIOCHUS

Antiochus Epiphanes, is given by See also:

• JEROME, JEROME KLAPKA (1859– )
• JEROME, ST (HIERONYMUS, in full EUSEBIUS SOPHRONIUS HIERONYMUS) (c. 340–420)

Jerome . There is no See also:

• PROOF (in M. Eng. preove, proeve, preve, &°c., from O. Fr . prueve, proeve, &c., mod. preuve, Late. Lat. proba, probate, to prove, to test the goodness of anything, probus, good)

proof of the assertion of See also:

• SOCRATES

Socrates, the ecclesiastical historian, and Augustine, that Porphyry was once a See also:

• CHRISTIAN
• CHRISTIAN, WILLIAM (1608-1663)

Christian . There is no See also:

• COMPLETE

complete edition of the works of Porphyry . See also:

• SEPARATE

Separate See also:

• EDITIONS

editions: Vita Plolini in R . Volkmann's edition of the Enneades of Plotinus (1883); Sententiae, by B . Mommert (1907); Vita Pythagorae, De antro nympharum, De abstinentia, Ad Marcellam, by A . See also:

• NAUCK, JOHANN AUGUST (1822-1892)

Nauck (1885); Isagoge et in Aristotelis categorias commentarium," by A . Busse in Commentaria in Aristotelem graeca (1887), iv . 1, with the See also:

• TRANSLATION

translation of Boetius (ed. with introd., S .

Brandt, 1906); fragments of the Chronica in C . W . See also:

• MILLER, HUGH (1802–1856)
• MILLER, JOAQUIN (CINCINNATUS HEINE) (1841- )
• MILLER, JOE (JosEPH or JosIAS( (1684-1738)
• MILLER, SAMUEL FREEMAN (1816-1890)
• MILLER, WILLIAM (1782-1849)
• MILLER, WILLIAM (1795-1861)
• MILLER, WILLIAM (1796–1882)
• MILLER, WILLIAM HALLOWES (18o1–188o)

Miller, Frag. list. graec . (1849), iu . 688; Quaestiones homericae, by H . See also:

• SCHRADER, EBERHARD (1836-1908)

Schrader (188o, 189o) ; Letter to Anebo in W . Pharthey's edition of Iamblichus De mysteriis (1857) ; De philosophia ex oraculis haurienda, by G . See also:

• WOLFF (less correctly WOLF), CHRISTIAN (1679-1754)
• WOLFF, CASPAR FRIEDRICH (1733-1794)
• WOLFF, JOSEPH (1795–1862)

Wolff (1856); fragments of the Adversus Christianos by A . Georgiades (See also:

• LEIPZIG

Leipzig, 1891); See also:

• ENGLISH

English trans. of the De abstinentia, De antro nympharum and Sententiae, by See also:

• THOMAS
• THOMAS (c. 1654-1720)
• THOMAS (d. 110o)
• THOMAS, ARTHUR GORING (1850-1892)
• THOMAS, CHARLES LOUIS AMBROISE (1811-1896)
• THOMAS, GEORGE (c. 1756-1802)
• THOMAS, GEORGE HENRY (1816-187o)
• THOMAS, ISAIAH (1749-1831)
• THOMAS, PIERRE (1634-1698)
• THOMAS, SIDNEY GILCHRIST (1850-1885)
• THOMAS, ST
• THOMAS, THEODORE (1835-1905)
• THOMAS, WILLIAM (d. 1554)

Thomas See also:

• TAYLOR
• TAYLOR, ANN (1782-1866)
• TAYLOR, BAYARD (1825–1878)
• TAYLOR, BROOK (1685–1731)
• TAYLOR, ISAAC (1787-1865)
• TAYLOR, ISAAC (1829-1901)
• TAYLOR, JEREMY (1613-1667)
• TAYLOR, JOHN (158o-1653)
• TAYLOR, JOHN (1704-1766)
• TAYLOR, JOSEPH (c. 1586-c. 1653)
• TAYLOR, MICHAEL ANGELO (1757–1834)
• TAYLOR, NATHANIEL WILLIAM (1786-1858)
• TAYLOR, PHILIP MEADOWS (1808–1876)
• TAYLOR, ROWLAND (d. 1555)
• TAYLOR, SIR HENRY (1800-1886)
• TAYLOR, THOMAS (1758-1835)
• TAYLOR, TOM (1817-1880)
• TAYLOR, WILLIAM (1765-1836)
• TAYLOR, ZACHARY (1784-1850)

Taylor (1823); of the Sententiae by T . See also:

• DAVIDSON, ANDREW BRUCE (1831–1902)
• DAVIDSON, JOHN (1857–1909)
• DAVIDSON, RANDALL THOMAS (1848– )
• DAVIDSON, SAMUEL (1807-1898)
• DAVIDSON, THOMAS (1817-1885)

Davidson in the See also:

• JOURNAL
• JOURNAL (through Fr. from late Lat. diurnalis, daily)

Journal of Speculative Philosophy, iii . (1869); of the De abstinentia by S . Hibberd (1857), and of the Ad Marcellam by A .

Zimmern (1896) . On Porphyry and his works generally see See also:

• FABRICIUS, GAIUS LUSCINUS (i.e. " the one-eyed ")
• FABRICIUS, GEORG (1516-1571)
• FABRICIUS, HIERONYMUS
• FABRICIUS, JOHANN ALBERT (1668-1736)
• FABRICIUS, JOHANN CHRISTIAN (1745-18o8)

Fabricius, Bibliotheca raeca (ed . Harles), v . 725; See also:

• EUNAPIUS

Eunapius, Vita philosophorum; See also:

• ARTICLE (from Lat. articulus, a joint)

article in Suidas; See also:

• LUCAS, CHARLES (1713–1771)
• LUCAS, JOHN SEYMOUR (1849– )
• LUCAS, SIR CHARLES (d. 1648)

Lucas See also:

• HOLSTENIUS, LUCAS

Holstenius, De vita et scriptis Porphyrii (See also:

• CAM (CAO), DIOGO (fl. 1480-1486)

Cam-See also:

• BRIDGE

bridge, 1655) ; J . E . See also:

• SANDYS, FREDERICK (1832-1904)
• SANDYS, GEORGE (1578-1644)
• SANDYS, SIR EDWIN (1561-1629)

Sandys, Hist. of Classical Scholarship (1906), i . 343: W . See also:

• CHRIST (Gr. X pLQTOS, Anointed)
• CHRIST, WILHELM VON (1831-1906)

Christ, Gesch. der griechischen Litteratur (1898), § 621; M . N . Bouillet, Porphyre, son role See also:

• DENS, PETER (1690-1775)

dens l'ecole neoplatonicienne (1864); A . I . Kleffner, Porphyrius der Neuplatoniker and Christenfeind (See also:

• PADERBORN (Lat. Paderae Fontes, i.e. the springs of the Pader)

Paderborn, 1896) ; on his philosophy, T .

Whittaker, The Neo-Platonists (See also:

• CAMBRIDGE
• CAMBRIDGE, EARLS AND DUKES OF
• CAMBRIDGE, RICHARD OWEN (1717-1802)

Cambridge, 1901), and NEOPLATONISM . 'PORPHYRY (Gr. irop4 peon, See also:

• LAT

Lat. purpureus, purple), in See also:

• PETROLOGY

petrology, a beautiful red volcanic See also:

• ROCK
• ROCK (O.Fr. rake, Sp. rota, Ital. rocca; possibly from a Lat. form rupica, from rupes, rock)
• ROCK, DANIEL (1799–187t)

rock which was much used by the See also:

• ROMANS
• ROMANS, EPISTLE TO THE

Romans for ornamental purposes when cut and polished . The famous red porphyry (porfido rosso antico) came from See also:

• EGYPT

Egypt, but its beauty and decorative value were first recognized by the Romans in the time of the See also:

• EMPEROR (Fr. empereur, from the Lat. imperator)

emperor See also:

• CLAUDIUS
• CLAUDIUS [TIBERIUS CLAUDIUS DRUSUS NERO GERMANICUS]
• CLAUDIUS, MARCUS AURELIUS
• CLAUDIUS, MATTHIAS (174o-1815)

Claudius . It was obtained on the See also:

• WEST
• WEST, BENJAMIN (1738-1820)
• WEST, NICHOLAS (1461-1533)

west See also:

• COAST (from Lat. costa, a rib, side)

coast of the Red See also:

• SEA (in O. Eng. sae, a common Teutonic word; cf. Ger. See, Dutch Zee, &c.; the ultimate source is uncertain)
• SEA, COMMAND OF THE

Sea, where it forms a See also:

• DIKE, or DYKE (Old Eng. dic, a word which appears in various forms in many Teutonic languages, cf. Dutch dijk, German Teich, Danish dige, and in French, derived from Teutonic, digue; it is the same word as " ditch " and is ultimately connected with the ro

dike 8o or 90 ft. thick . For a long time the knowledge of its source was lost, but the original locality, marked by many See also:

• ANCIENT
• ANCIENT (also spelt ANTIENT; derived, through the Fr. ancien, old, from the late Lat. antianum, from ante, before)

ancient quarries, has been re-discovered at See also:

• JEBEL (plur. jibed)

Jebel Dhokan, and the See also:

• STONE
• STONE (0. Eng. shin; the word is common to Teutonic languages, cf. Ger. Stein, Du. steen, Dan. and Swed. sten; the root is also seen in Gr. aria, pebble)
• STONE, CHARLES POMEROY (1824-1887)
• STONE, EDWARD JAMES (1831-1897)
• STONE, FRANK (1800-1859)
• STONE, GEORGE (1708—1764)
• STONE, LUCY [BLACKWELL] (1818-1893)
• STONE, MARCUS (184o— )
• STONE, NICHOLAS (1586-1647)

stone is again an article of See also:

• COMMERCE
• COMMERCE (Lat. commercium, from, cum, together, and rnerx, merchandise)

commerce . In a dark red ground-See also:

• MASS (O.E. maesse; Fr. messe; Ger. Messe; Ital. messa; from eccl. Lat. missa)
• MASS, IN

mass it contains many small 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 or See also:

• ROSE
• ROSE (Rosa)
• ROSE, GEORGE (1744-1818)
• ROSE, HUGH JAMES (1795—1838)
• ROSE, WILLIAM STEWART (1775-1843)

rose-red See also:

• PLAGIOCLASE

plagioclase felspars, See also:

• BLACK
• BLACK, ADAM (1784-1874)
• BLACK, JEREMIAH SULLIVAN (1810–1883)
• BLACK, WILLIAM (1841-1898)

black shining prisms of See also:

• HORNBLENDE

hornblende, and small plates of See also:

• IRON [symbol Fe, atomic weight 55.85 (0=16)]

iron See also:

• OXIDE

oxide . The red colour of the felspars and of the ground-mass is unusual in rocks of this See also:

• GROUP

group, and arises from the partial See also:

• CONVERSION (Lat. conversio, from convertere, to turn or ,change)

conversion of the plagioclase See also:

• FELSPAR, or FELDSPAR

felspar into thulite and See also:

• MANGANESE (symbol Mn; atomic weight, 54.93 (0=16)], a metallic chemical element. Its dioxide (pyrolusite)

manganese-See also:

• EPIDOTE

epidote . These minerals also occur in thin See also:

• VEINS

veins See also:

• CROSSING

crossing the rock . Manyspecimens show effects of crushing and in extreme cases this has produced brecciation . Another famous porphyry, hardly less beautiful, is the verde See also:

• ANTIQUE (Lat. antiquus, old)

antique, porfido verde antico, or marmor lacedaemonium viride of See also:

• PLINY, THE ELDER
• PLINY, THE YOUNGER

Pliny, which was obtained between Lebetsova and Marathonisi in See also:

• PELOPONNESUS (" Island of Pelops ")

Peloponnesus . It has the same structure as the red porphyry as it contains large white or See also:

• GREEN, A
• GREEN, ALEXANDER HENRY (1832—1896)
• GREEN, DUFF (1791—1875)
• GREEN, JOHN RICHARD (1837—1883)
• GREEN, MATTHEW (1696-1737)
• GREEN, THOMAS HILL (1836-1882)
• GREEN, VALENTINE (1739–1813)
• GREEN, WILLIAM HENRY (.1825–1900)

green felspars in a See also:

• FINE

fine ground-mass . The green colour arises from the abundant formation of See also:

• CHLORITE

chlorite and epidote in the large felspars and throughout the rock .

In ancient times it was much used as an ornamental stone, these two varieties of porphyry making a fine contrast with one another . Green porphyries are not so rare as red . A similar rock is obtained at Lambay See also:

• ISLAND (O.E. ieg =isle, +land')

Island near See also:

• DUBLIN

Dublin . They are still used extensively, especially for small ornaments . Large pieces are difficult to obtain See also:

• FREE

free from flaws, and See also:

• MARBLE (from Lat. marmor, Gr. pApµapos, shining stone)

marble is preferred for mural work, not only because of the greater variety of patterns but also because it is much softer and more easily cut and polished . Many igneous rocks possess the structure which characterizes these porphyries (see PETROLOGY, See also:

• PLATE

Plate III.) : the presence of scattered crystals of larger See also:

• SIZE

size in a fine-grained ground-mass . Most lavas, and many of the rocks which occur as dikes and sills, have porphyritic structure . These may be called porphyries and this See also:

• TERM

term has consequently been applied to a great variety of rocks, e.g. See also:

• DIORITE (from the Gr. S&oi4eiv to distinguish, from hA through, Epos, a boundary)

diorite-porphyry, See also:

• GRANITE (adapted from the Ital. granite, grained; Lat. granum, grain)

granite-porphyry, greenstoneporphyry, See also:

• AUGITE

augite-porphyry, liebenerite-porphyry, &c . More recently the use of the term has been restricted to a See also:

• SERIES (a Latin word from serere, to join)

series of rocks which are of intrusive origin and contain much porphyritic felspar (with or without See also:

• QUARTZ

quartz or See also:

• NEPHELINE

nepheline) . The porphyritic intrusive rocks with large crystals of augite, See also:

• OLIVINE

olivine, See also:

• BIOTITE

biotite, and hornblende are for the most part grouped under the See also:

• LAMPROPHYRES (from Gr. Xaurp6s, bright, and the terminal part of the word porphyry, meaning rocks containing bright porphyritic crystals)

lamprophyres; while the term porphyry is rarely now applied to any of the effusive rocks or lavas . Furthermore, it has become usual to subdivide the intrusive porphyries into two classes; in one of these the phenocrysts are mainly See also:

• ORTHOCLASE

orthoclase, in the other mainly plagioclase felspar . The first series is known as the " porphyries," while the second group is called " porphyrites." There are porphyries which correspond chemically and mineralogically to granites, syenites, and nepheline-syenites; while the porphyrites form a parallel series to the diorites, norites and gabbros .

In each See also:

• CASE
• CASE, JOHN (d. 1600)

case the porphyritic type occurs generally as dikes and thin sheets which consolidated beneath the See also:

• SURFACE

surface but probably at no great See also:

• DEPTH

depth (hypabyssal rocks); while granite, See also:

• GABBRO

gabbro and the other holocrystalline non-porphyritic rocks belong to the plutonic or abyssal group which cooled very slowly at great depths and under enormous pressure . The See also:

• PRINCIPAL

principal subdivisions of the group are the granite-porphyries, the See also:

• SYENITE

syenite-porphyries and the elaeolite-porphyries . In all of them porphyritic orthoclase or See also:

• ALKALI

alkali felspar is the characteristic See also:

• MINERAL

mineral . The granite-porphyries and quartz-porphyries (q.v.) consist mainly of orthoclase, quartz and ferro-magnesian mineral, usually biotite but sometimes hornblende, augite or See also:

• ENSTATITE

enstatite . Granite-porphyries are exceedingly See also:

• COMMON

common in all regions where See also:

• ACID (from the Lat. root ac-, sharp; acere, to be sour)

acid intrusive rocks occur . Many granite masses are surrounded by dikes of this See also:

• KIND (O. E. ge-cynde, from the same root as is seen in " kin," supra)

kind, and in some cases the chilled margin of a granite consists of typical porphyry . The syenite-porphyries, like the syenites, are less common than the granite-porphyries and granites . They are characterized by an abundance of orthoclase and a scarcity or See also:

• ABSENCE (Lat. absentia)

absence of quartz . The phenocrysts are orthoclase (and See also:

• OLIGOCLASE

oligoclase), biotite, hornblende or augite; the ground-mass is principally alkali felspar with sometimes a little quartz . In many specimens the felspars of the second See also:

• GENERATION (from Lat. generare, to beget, procreate; genus, stock, race)

generation form a See also:

• MOSAIC (corresponding to Lat. opus musivum, from Gr. µovoeiov, an artificial grotto often decorated with mosaics; the word is only found in the sense of mosaic in late Greek, which generally uses k oXI yrlµa)

mosaic of See also:

• ILL

ill-shaped grains, in others they are little rectangular crystals which may have a fluxion arrangement (orthophyric type of ground-mass) . Some of the rocks formerly known as orthoclase-porphyries belong to this group; others are ancient trachytic lavas (orthophyrea) . Closely related to the syenite-porphyries is the rhomben-porphyry of See also:

• SOUTH
• SOUTH, ROBERT (1634–1716)

south See also:

• NORWAY
• NORWAY (Norge)

Norway and West See also:

• AFRICA
• AFRICA, ROMAN

Africa .

In these the large felspars have rhomb-shaped sections owing to their See also:

• PECULIAR

peculiar crystalline development . Olivine, augite and biotite occur in these rocks, but there is no quartz or soda-See also:

• LIME
• LIME (O. Eng. lim, Lat. limes, mud, from linere, to smear)

lime felspar . The porphyritic felspars contain both soda and potash and belong to anorthoclase . Rhomben-porphyries occur as dikes connected with the syenites (laurvikites of See also:

• SOUTHERN

southern Norway), and many See also:

• ICE (a word common to Teutonic languages; cf. Ger. Eis)

ice-See also:

• BORNE, KARL LUDWIG (1786–1837)

borne boulders of these rocks have been found among the See also:

• DRIFT (from "drive ")

drift deposits of the See also:

• EAST
• EAST, ALFRED (1849- )

east of See also:

• ENGLAND
• ENGLAND, THE CHURCH OF

England . Elaeolite- and See also:

• LEUCITE

leucite- (syenite) porphyries form apophyses and dikes around nepheline- and leucite-syenite intrusions . The former contain porphyritic nepheline which is often weathered to soft, finely crystalline aggregatesof white See also:

• MICA

mica and other secondary in all respects except in their being less coarsely crystalline . products as in the well-known liebenerite-porphyry of See also:

• TIROL (or TYROL 1)

Tirol and Norite-porphyrites have porphyritic plagioclase (See also:

• LABRADORITE, or LABRADOR SPAR

labradorite gieseckite-porphyry of See also:

• GREENLAND (Danish, &c., Gronland)

Greenland . The felspars of these rocks are See also:

• ALBITE

albite, orthoclase and anorthoclase. and they often See also:

• CON

con- usually) with See also:

• HYPERSTHENE

hypersthene or See also:

• BRONZITE

bronzite, often altered to bastite. See also:

• TAIN

tain soda-augite and amphiboles . Elaeolite-porphyries occur They accompany norite masses in See also:

• NAHE

Nahe (See also:

• PRUSSIA
• PRUSSIA (Ger. Preussen; Lat. Borussia)

Prussia) and Tirol, along with nepheline-syenites in such districts as the Serra de They have vitreous forms which are described as andesitic-See also:

• MONCHIQUE

Monchique, south Norway, See also:

• KOLA

Kola, See also:

• MONTREAL

Montreal . Allied to them are pitchstones or hypersthene-andesftes . the tinguaites (so called from the Serra de Tingua, Rio de Janeiro, See also:

• BRAZIL
• BRAZIL, or BRASIL

Brazil), which are See also:

• PALE (through Fr. pal, from Lat. palms, a stake, for paglus, from the stem pag- of pangere, to fix; " pole " is from the same original source)

pale green rocks with abundant alkali felspar nepheline, needles of green aegirine, and sometimes biotite and cancrinite . As a See also:

• RULE

rule, however, these. are not porphyritic .

Some authors group the tinguaites with the aplites rather than the porphyries . Grorudites are quartz-tinguaites free from nepheline, and solvsbergites are tinguaitic rocks in which neither quartz nor nepheline occur . The two last varieties have been described from the See also:

• CHRISTIANIA (officially KRISTIANIA)

Christiania See also:

• DISTRICT

district in Norway, but tinguaites are known with nepheline-syenites in many parts of the See also:

• WORLD

world, e.g . Norway, Brazil, See also:

• PORTUGAL

Portugal, See also:

• CANADA

Canada, See also:

• SWEDEN
• SWEDEN [Sverige]
• SWEDEN, NORWAY AND

Sweden, Greenland . The following analyses of porphyries of different types will show the chemical See also:

• COMPOSITION
• COMPOSITION (Lat. compositio, from componere, to put together)

composition of a few selected examples:- Si02 Al203 Fe2O3 FeO MgO CaO K2O Na2O See also:

• H2O (combined)

H2O I . 72.51 13.31 tr . 3.87 1.50 0.60 6.65 0.43 0.60 II . 67.18 16.65 0.55 2.15 I.54 2.35 2.91 4.03 0.75 IV . 58.82 2I•o6 3.26 0.70 1.38 3.03 3.70 6 . 3 I.26 V .