Crystals have the form of hexagonal plates bounded at their edges by faces of a hexagonal prism and pyramids, which are deeply striated horizontally. More frequently, however, the mineral is massive, with a laminar or granular structure. The colour is bronze yellow and the lustre metallic; the streak is greyish-black. The hardness is 4 and the specific gravity 4 58-4-64. The mineral is magnetic, sometimes with polarity, and it is therefore often called “ magnetic pyrites."
Pyrrhotite occurs in metalliferous veins, and as grains and plates disseminated through various rocks. In the gabbros and norites of Norway and Sweden it has been concentrated by magmatic differentiation at the margins of the igneous masses. Large bodies of massive pyrrhotite occur at Bodenmais in Bavaria and in Wheal lane near Truro in Cornwall. Crystallized specimens are from the metalliferous veins at Morro Velho in Brazil, Kongsberg in Norway, and Andreasberg in the Harz. Crystals of pyrrhotite have also been observed in meteoric stones; but iron sulphide appears more commonly in meteorites, especially in meteoric irons, as troilite (FeS), which, if really distinct from pyrrhotite, has not been met with in terrestrial rocks. (L. J. S.)
PYRRHUS (c. 3I8'272 B.c.), king of Epirus, son of Aeacides, and a member of the royal family of the Molossians. He claimed descent from Pyrrhus, the son of Achilles, and was also connected with the royal family of Macedonia through Olympias, the mother of Alexander the Great. When a mere lad he became king of the wild mountain tribes of Epirus, and learned the art of war in the school of Demetrius Poliorcetes and his father Antigonus. He fought by their side at the battle of Ipsus (301) in Phrygia, in which they were decisively defeated by the combined armies of Seleucus Nicator and Lysimachus. Soon afterwards he was' sent to the court of Ptolemy of Egypt at Alexandria as a pledge for the faithful carrying out of a treaty of alliance between his brother-in-law Demetrius and Ptolemy. Through Ptolemy, whose step»daughter Antigone he married, Pyrrhus was enabled to establish himself firmly on the throne of Epirus, and became a formidable opponent to Demetrius, who was now king of Macedonia and the leading man in the Greek world. He defeated one of Dernetrius's generals in Aetolia, invaded Macedonia, and forced Demetrius to conclude a truce with him. For about seven months Pyrrhus was in possession of a large part of Macedonia, Demetrius finding it convenient to make this surrender on condition that Pyrrhus did not meddle with the affairs of Peloponnesus. But in 286 he was defeated by Lysimachus at Edessa, driven out of Macedonia, and compelled to fall back on his little kingdom of Epirus. In 281 came the great opportunity of his life. An embassy was sent to him from the Greek city Tarentum in southern Italy with a request for aid against Rome, whose hostility the Tarentines had recklessly provoked. After some hesitation on the part of the Tarentines, Pyrrhus's conditions were accepted, and a treaty was concluded. His general Milo crossed with a body of troops and occupied the citadel. Pyrrhus soon followed with a miscellaneous force of about 25,000 men (partly furnished by Ptolemy Ceraunus of Macedonia) and some elephants. The Tarentines and Italian Greeks shrank, however, from anything like serious effort, and resented his calling upon them for men and money. Rome meantime levied a special war contribution, called on her subjects and allies for their full contingent of troops, and posted strong garrisons in all towns of doubtful fidelity. She was now the dominant power in Italy, but her position was critical, as in the north she had had trouble with the Etruscans and the Gauls, while in the south the Lucanians and the Bruttians were making common cause with Tarentum and the Greek cities. For the first time in history Greeks and Romans met in battle at Heraclea near the shores of the Gulf of Tarentum, and the cavalry and elephants of Pyrrhus secured for him a complete victory over the consul M. Valerius Laevinus, though at so heavy a cost as to convince him of the great uncertainty of final success (hence is derived the phrase of a Pyrrhic victory). Although he now had the Sarnnites as well as the Lucanians and the Bruttians and all the Greek cities of southern Italy with him, he found every city closed against him as he advanced on Rome through Latium. The peace negotiations, carried on by the skilful diplomatist Cineas, the minister of Pyrrhus, led to no result; the senate seemed inclined to come to terms, but the fiery and patriotic eloquence of the aged and blind Appius Claudius (the censor) carried the day. Cineas was ordered to leave the city at once and to tell his master that Rome could not negotiate so long as foreign troops remained on the soil of Italy. In the second year of the war (279), Pyrrhus again defeated a Roman army at Asculum (mod. Ascoli) in Apulia, but Rome still had armies in the field and h'er Italian confederation was not broken up. For a while he quitted Italy for Sicily, at the invitation of the Syracusans, with the idea of making himself the head of the Sicilian Greeks and driving the Carthaginians out of the island. In his military operations he was on the whole successful; and Rome and Carthage, in face of the common danger, concluded an offensive and defensive alliance against him. He passed three years in Sicily, but offended the Greek cities, which he governed in the fashion of a despot. Finding that he could no longer hold Sicily in face of the ill feeling thus aroused, and reproached by the Samnites for having deserted them, he decided to return to Italy. On the voyage he was attacked by the Carthaginians and lost several vessels. When he reached Italy, the Tarentines and the other Greek cities, having lost confidence in him, refused to supply him with men or money. Thoroughly disheartened, he made one more effort and engaged a Roman army at Beneventum (275) in the Samnite country, but his arrangements miscarried, and he was defeated with the loss of his camp and the greater part of his army. Nothing remained but to go back to Greece. He left a garrison in Tarentum and returned the following year to his home in Epirus after a six years' absence. The brief remainder of his life was passed in camps and battles, without any glorious result. He gained a victory on Macedonian soil over Antigonus Gonatas, king of Macedonia, whose troops hailed him as king. In 273 he was invited into Peloponnesus by Cleonymus to settle by force of arms a dispute about the royal succession at Sparta. He besieged the city, but was repulsed with great loss. Next, at the invitation of a political faction, he went to Argos, where, during a fight by night in the streets, he was struck on the head by a huge tile. He fell from his horse, and was put to death by one of the soldiers of Antigonus.
Pyrrhus was a brilliant and dashing soldier, but he was aptly compared to a gambler who made many good throws with the dice, but could not make proper use of them in the game. He obtained no lasting results, and was never more than a captain of mercenaries, yet there was something chivalrous about him which seems to have made him a general favourite. After his death Macedonia had, for a time at least, nothing to fear, and the liberty of Greece was quite at the mercy of that power. Pyrrhus wrote a history of the art of war, which is praised by Cicero, and quoted by Dionysius of Halicarnassus and Plutarch. The chief ancient authority for the life of Pyrrhus is Plutarch; see also Polybius xviii. II, and elsewhere; Dion. Halic. xviii. I, xix. 6-9; Pausanias i. 13; Justin xviii. I, 2, xxiii. 3, xxv. 4, 5. Modern monographs by G. F. Hertzberg, “ Rom und Konig Pyrrhus “ (popular: in O. ]ager's Darstellungen aus der rzimischen Geschichte, 1870); R. von Scala, Der Pyrrhische Krieg (1884), with map of Roman garrison system in 281; R. Schubert, Geschichte des Pyrrhus (1894), with full list of authorities; also ROME: History, “The Republic.”
PYRROL, C4H5N or C4H4-NH, an organic base found in coaltar and Dippel's oil. It may be synthetically prepared by the dry distillation of ammonium mucate, or, better, by heating it with glycerin to 180-200° C. (H. Schwanert, Ann., 1860, 116, p. 2 57), by passing the vapour of diethylamine through a redhot tube; by distilling succinimide with zinc dust (C. A. Bell, Ber., 1880, 13, p. 877); by distilling calcium pyroglutaminate: HO2C'CH(NH2)'CH2'CHz'CO2H = C4H4NH-l-CO2-l-2H2O (L. Haitinger, Monats., 1882, 3, p. 228); and by boiling succinic dialdehyde with ammonia and glacial acetic acid (C. Harries, Bar., 1901, 34, p. 1497). It is a feebly basic, colourless liquid which boils at 130° C., and possesses a smell resembling that of chloroform. It is slightly soluble in water, and turns brown on exposure to air. It has to some extent the character of a secondary amine; the hydrogen of the imino group can be replaced by potassium. It is resinified by the action of concentrated mineral acids. On warming solutions of pyrrol in