PYROXENE. 580 called also malacolite, or alalite, a calcium-mag- nesium pyroxene, whose color varies from pure white and yello« ish or grayish wliite to green ; hedenhcrgite, a ealcium-iron pyroxene of a black color; schcfferite, a manganese pyroxene some- times containing iron, of a brownisli color; and augite, an aluminum pyroxene sometimes con- taining small (luantities of the alkalies, of a black color. These varieties are common miner- als, and are found in crystallized limestone aiul dolomite, and frecjucntly in the older rocks. I'y- ro.xene is an essential constituent of many igne- ous or erujjtive rocks, and uitU labradorite or anorthite and magnetite it forms basalt. Cer- tain varieties, as diopside, have been obtained as furnace products at iron works. Artificial crystals of diopside have been obtained by the action of silicon chloride on magnesia. PYROX'ENITE (from Ok. vip, pur. fire + l^vot, iviiiiiK. guest). An igneous rock of nltra- liasic composition fri'c from feldspar, and ehielly coiu])osed of one or mcu'e varieties of ])vroxene or ami)liibole, and sometimes magnetite or ilmenite. The average chemical composition of pyroxenite is: Silica, 53 per cent.; alumina, 4 per cent.; sesquioxide of iron, 2 per cent. ; protoxide of iron, 7 ])er cent.; oxide of lime, 1.3 per cent.; magnesia, 21 per cent.; oxides of the alkalies, 1 per cent. Pyroxenites easily sutler alteration from weathering, the princi|)al products being tale (soapstone) and serpentine. They are closely allied to the pi'ridotites (q.v.). PYROXYLIC SPIRIT. See IMetiiyl Alco- iKir.. PYROX'YLIN. A name for gimeotton (q.v.). PYRRHIC DANCE (Qk. i) Xlvpplx-n, 1>f 'J'yr- rliicln'j. The oldest and most famous of the an- cient Greek war dances. As to its origin and name accounts varieil, some attributing it to a Cretan or Spartan named PA-rrhichos, others to Pyrrhos, son of Achilles, others to the Dioscuri or Curetes. The Cretan name is said to have been irpiJXis, ?»■,)/'/«. There can be little doulit that the dance originated among the Doiians of Crete or Laeonia, and it was especially cultivated by the Spartans as valua!)le training for the soldier. It seems to have l)een inesented by a chorus of armed youths, who diviiled into two bands and represented in pantomime attack and defense, including the feints and parries needed in individual contest. It was also danced as a solo, and sometimes by women, as is clear from Xenophon's account in the Aiiabn.<ii.'i and the tes- timony of the vases. At Athens it was cultivated by the Epliclii, and danced in the competitions of the Panatheniva. In later times a, Bacchic ele- ment was introduced and we are told the ad- ventures of Dionysus were depicted. In Rome it was very pn])ular as a i)antoniimic spectacle. The time of the nuisie is said to have been rapid, and in Greek metre two short syllables (- w) are known as a Pyrrhic foot. This, however, oc- curs rarely, and is always to be measured as containing three metrical units, the smallest number which can form a foot. PYRRHIC VICTORY. A phase denoting a success won at a ruinous cost, referring to the battle of Ascuhun, in which Pyrrhus gained the victory' over the Romans with such heavy losses that he is said to have exclaimed, ". other such victory, and Pyrrhus is destroyed." PYRRHUS. PYRRHO, jiir'rA (Lat., from Gk. Uippior, I'yrrlibn (c. 3U5-C.275 B.C.). A Greek philoAo- pher born in Elis; the founder of the Skeptical School of pliilosoiiliy. lie was a painter in his youth, but later was attracted to philosophy by the works of Demoeritus and became the pupil of Bryson, a disciple of Stilpo. Afterwards lie attached himself to Anaxarehus. and with him accompanied Alexander the Great on his expedi- tion to the East, where, according to Diogenes Laertius, he became aeiiuainted with the teach- ings of the Persian Magi and the Indian Gyninos- opliists. During much of his long life he lived in retirement. He was so highly esteemed by his fellow-citizens that they made him their chief ])riest and honored him with .a statue after his death; the Athenians gave him the riglits of citizenship. As Pyrrlio lef£ no writings, little is certainly known of his doctrine; the cliief source of information is the work of his follower, Timon the Sillographer, The main principle of his teaching seems to have been that to attain the liighest good, happiness, we must know the nature of things and the relation we should bear to them. But since we know things only as they seem to us, their real nature cannot be definitely apprehended, and hence objective knowledge Is impossible of attainment. 'I'herefore the correct' attitude for the philosopher is comiilcte .suspense of judgment, and in this lies freedom from trouble and peace, which is man's chief good. Consult; Waddington, I'l/rrhoii ct le Pi/rihonismc (Paris, 1877); Zeller. I'hiUi.so/ihir dcr (Iricchcn, vol. iii. (3d ed., Leipzig, 1880); Ueberweg, His- torii of I'Jiihsophi/, Eng. trans., vol. i. (New York, 1872); Erdinann, Uhtorti of Philosophi/, Eng. trans., vcd. i. (New York, i8!m), PYR'RHOTITE (from Gk. wvpp6s. pyrrhns, reddish, from wvp, pyr, fire). A mineral iron sulphide, frequently containing nickel, that crys- tallizes in the hexagonal system, has a metallic lustre, and in color is bronze-yellow to copper- red. It occurs with magnetite and ajiatite, also with other suljihidcs in the older rocks, as well as sometimes in meteorites. This mineral is found in Norway, Sweden, Bohemia, the llarz. Saxony. England, and Brazil; while in the I'nited States it is found in various parts of New England, New York, New .Jersey, Pennsyl- vania, and in Tennessee. PYRRHUS, pir'riis (Lat., from Gk. llvppii) (c. 318-272 n.c. ). A King of E|)irus, son of .ICaci- des and Plithia, and a distant kinsman of Alex- ander the Great. According to one account he was a descendant of Ncoptolemus (otherwise called Pyrrhus), son of Achilles. When .Eacides was deposed by a faction of his ])eople and driven from his kingdom, Pyrrhus, who was then but an infant two years of age. was rescued by some faithful attendants of the King and carried to Glaueias, King of a tribe of the lllyrians. By him he was restored to his kingdom when twelve years old, but in 302 was again driven out and took refuge with Demetrius Poliorcetes. After serving in the battle of Ipsus, he went as a ho-st- age for Demetrius to Egypt, where he married the .stepdaughter of Ptolemy Soter. Thence returning to Epirus, he regained possession of his throne, and immediately directed his at- tention to the conquest of Macedonia. He ob- tained possession of the western part of that conntrv, and, when his former friend Demetrius
