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of Conde and the dukes of Lorraine, Sa- between two square brass rods, fixed on a voy, and Modena, and the prince of Mo- brass plate twenty-four inches long, ball naco (the two first especially), were left in an inch asunder at one extremity, and 03 statu quo. In consequence of this peace, jnch at the other. The brass rods wer Louis XIV married Maria Theresa, eldest divided into inches and tenths, making i daughter of Philip IV, who, in 1660, re- all 240 divisions, or degrees. When pieces nounced all right of inheritance to the of clay, baked in Wedgewood's mande, Spanish throne. Louis XIV, however, are exposed to heat, they shrink in their afterwards made pretensions to this right, dimensions, and the degree of shrinking from which arose the devolution war, and was believed to be proportional to the the war of the Spanish succession. (See temperature. This was the foundation of Aix-la-Chapelle, Peace of, and Utrecht, his instrument. The heat to which tb" Peace of.)

piece of clay was exposed was indicate, PYRITES ; a genus of inflammable sub- when its shrinkage was measured be stances, composed of sulphur, which has tween the brass rods. If exposed to the dissolved or saturated itself with metals. heat at which silver melts, it advance

PYRMONT, or Neustadt PYRMONT; a between the brass rods to 22°, or 2? town in the principality of Waldeck, situ- inches; if to the melting point of gold, s, ated in a pleasant valley on the Emmer, 32°; and if to the melting point of car thirty-three miles south-west of Hanover. iron, to 130°; and so on. But this pf It is well built, with delightful walks, and rometer of Wedgewood has been lon: is famous for its thermal waters, which are laid aside, in consequence of the observayearly visited by 1800 strangers. The tion, that if a piece of this clay was lors waters are saline. (See Mineral Waters.) exposed to a low temperature, it shru. In the vicinity are the ruins of the old as much in its dimensions as if it by. castle of Pyrmont, or Schellpyrınont, and been exposed for a short time to a mur the cave called Dunsthöhle, from which higher temperature. In 1803, Guyton oissues carbonic acid gas. There is also Morveau presented to the French insthere a colony of Quakers, called Fried- tute a pyrometer of platina, which meas ensthal (Vale of Peace).

ured high temperatures by the expansi : PYROCHLORE; a mineral recently de- of this refractory metal. An improve tected in the zircon sienite of Freder- ment of this instrument was brought foricksværn, in Norway. It occurs crystal- ward by Mr. Daniel in 1821, which corlized in regular octahedrons; specific gray- sisted of a bar of platina 10 inches long ity, 4.2; scratches fluor; streak brown; and 0.14 inch in diameter. It is placed i fracture conchoidal, without any trace of a tube of black lead or earthen ware, na cleavage; lustre between vitreous and the difference between the expansion ( resinous. Its color is reddish brown, and the platina bar and the earthen ware tule ou the fresh surface almost black; in thin is indicated on a circular scale. This py: splinters, translucent. It consists of titanic rometer indicates a change of about 70 ! acid 62.75, lime 12.85, oxide of uranium Fahrenheit; or, in other words, 1° of Du5.18, oxide of cerium 6.80, oxide of man- jel is equal to 70 of Fahrenheit. The farganese 2.75, oxide of iron 2.16, oxide of lowing are some of the results obtaine zinc 0.61, water 4.2, fluoric acid undeter- by this instrument: mined, avd magnesia a trace.

Daniel. PYROLIGNEOUS Acid. (See Vinegar.)

Boiling point of mercury, 920 044 PYROMETER; an instrument for the Fusing point of tin, measurement of temperatures above those

bismuth, 66 402 which we are able to estimate by the

lead, 87 mercurial thermometer. Mercury boils at

zinc, 94 660°, above which point it is incapable of

brass, 267 measuring heats; although many temper

silver, 319 atures connected with the most common

copper, 364 processes are greatly above this point, as,

gold, 370 230 for example, the heat of a common fire,

cast iron, 497 3473 the melting point of silver, copper, and Red heat just visible in gold. The first pyrometer was that in

daylight,

140 vented by Mr. Wedgewood. It consisted Heat of a common fire, 103 1141 of small pieces of clay from Cornwall, PYROPHORUS ; an artificial produca moulded into cylinders of a determinate which takes fire on exposure to the ur". size, and baked in a low red heat. These It is prepared by several methods. T« pieces were of just such a size as to enter Oldest way of proceeding is as follows:

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PYROPHORUS–PYROXYLIC SPIRIT.

439 Four or five parts of burnt alum are min- a bed of magnetic iron ore, alorg with gled with two of charcoal powder. The calcareous spar and hornblende, in Bjelke's mixture is introduced into a vial or mat- mine in Nordmark, in Wermeland. rass, with a neck of about six inches long. PYROTECHNY is, properly speaking, the The vial is filled about two thirds full, and science which teaches the management put into a crucible, the bottom of which and application of fire ; but, in a more is covered with sand. The body of the limited sense, and as it is more commonly flask is also surrounded with sand, after used, it refers chiefly to the composition, which the crucible is put into a furnace, structure and use of artificial fire-works. and surrounded with red-hot coals. The The ingredients are, 1. saltpetre, purified fire is gradually increased until the flask for the purpose ; 2. sulphur; and, 3. charbecomes red hot, at which temperature it coal. Gunpowder is likewise used in the is maintained for about a quarter of an composition of fire-works, being first hour. As soon as the vessel is become ground, or, as it is technically termed, cool enough to be handled, the vial is mealed. Camphor and gum-benzoin are taken out of the sand, and the contents employed as ingredients in odoriferous transferred into a dry and stout glass, fire-works. The proportions of the matemade warm, which must be secured with rials differ very much in different firea glass stopper. Whenever this mixture works, and the utmost care and precauis poured out in the air, it takes fire. A tion are necessary in the working them to pyrophorus may be prepared by mixing a state fit for use, and then in the mixing. three parts of alum with one of wheat When stars are wanted, camphor, alcoflour, and calcining them in a vial, as in the hol, antimony, and other ingredients, are above case. Tartrate of dead, also, on be- required, according as the stars are to be ing heated in a glass tube until it becomes blue, white, &c. In some cases, gold and converted into coaly matter, gives rise silver rain is required; then brass-dust, to a beautiful pyropborus. But the py-steel-dust, saw-dust, &c., enter into the rophorus invented by doctor Hare of Phil- composition. Hence the varieties may be adelphia is the most remarkable. It is almost indefinite. With respect to color, formed from heating a mixture of three sulphur gives a blue, camphor a white or parts lampblack, four calcined, alum and pale color, saltpetre a clear white yellow, eight pearlashes, in a gun-barrel. The sal-ammoniac a green, antimony a reddish, mixture is maintained at a cherry-red heat rosin a copper color. about one hour, or until it ceases to give PYROXENE, or Augite. (See Augite.) off inflammable gas at the orifice of the PYROXYLIC SPIRIT. When wood is tube, after which it is withdrawn from the distilled, the products are water, acetic turbace, and closely corked from the air. acid, pyroxylic acid, empyreumetic oil, and When cold, if poured from the gun-barrel a black matter, which is considered as into the air, it immediately glows and analogous to pitch, or, rather, tar. When takes fire; and more especially if breathed the watery portion, freed as well as possiupon, or slightly moistened. This pyroph- ble mechanically from the tar, is distilled orus may be preserved in its full activi- at a low heat, the first portion that comes ty for a year or more, if well corked up over is the pyroxylic acid, which may be from the air, but it requires much caution freed from acetic acid by agitation with in disengaging it from the tube ; for it has lime or magnesia, and subsequent distillaheen known to explode, with great vio- tion at a low temperature ; but it is still lence, simply on introducing into it an iron impure from the presence of empyreuramrod. This compound appears to owe matic oil. To free it completely from this its energy to its containing the sulphuret impurity, it must be mixed with its own of potassium.

weight of sulphuric acid, and the mixture PYROPHYSALITE. (See Topaz.). be subjected to distillation. Thus purified,

PYROSMALITE ; a lamellar substance, it is a transparent and colorless liquid, havfound also in six-sided tables, of a shining ing a strong and pungent smell, which has lustre; translucent; brittle; specific grav- been compared to that of ants, and also to ity 3.08. It is soluble in muriatic acid, the odor of acetic ether. Its taste is strong, with a residuum of silex. It gives out the hot, pungent, and very disagreeable. Speodor of chlorine when heated before the cific gravity, in its most concentrated state, blow-pipe, and becomes attractable by the 0.8121. Its boiling point is 150°. When magnet. Its constituents are peroxide of completely freed from acetic acid, it does iron 21.81, protoxide of manganese 21.14, not redden vegetable blues. It burns with sub-muriate of iron 14.09, silex 35.85, a very pale yellow flame, inclining to blue, lime 121, water and loss 5.9. It occurs in but the light is considerably greater than

that given out by alcohol. It burns all with the system of Democritus, who beli away, without leaving any residue, and the that, except the immediate elements of only products are carbonic acid and wa- bodies (atoms), nothing was real, and the ter. It dissolves in alcohol in any propor- all perception was subjective. (See 0. tion. With water it becomes opaque, ow- jective.) . He was confirmed in these ing, probably, to a small quantity of oil it views by the doctrines of Socrates, & still contains. It dissolves readily in oil whom, in his character, he bore a gree of turpentine, and in liquid potash, acquir- resemblance. Cicero mentions bim esing, at the same time, a yellowish color. pressly among the disciples of Socrates When the solution of this spirit in potash and his scepticism is allied to the irony or is distilled, we are able to obtain it per- that philosopher. Led, by his temperafectly pure from every portion of oil. ment and his manner of life, to esteein a When this spirit is mixed with nitric acid uninterrupted tranquillity the great object and distilled, an ethereal liquid comes of all philosophy, believing that nothing over, possessed of an exceedingly pungent tended so much to destroy this quiet & smell, and acting strongly on the nose and the interminable disputes of the schoos eyes. It burns with a bluish flame. The of the Dogmatists, and that uncertains specific gravity of this vapor is 1.94. was increased by their contentions, he de. PYRRHA. (See Deucalion.)

termined to seek, in some other way, the PyrrhiChius. (See Rhythm.)

peace which he despaired of finding in PYRRHO, a Grecian philosopher of Elis, dogmatical philosophy. This made hin founder of the Pyrrhonian or ancient a sceptic. Pyrrho left no writings. His sceptical school, flourished about 340 B.C., friend and scholar, Timon, first wrote cu and was probably born about the 101st the subject of scepticism, but his writing Olympiad. In his youth he studied the are lost. It is only froin the works of his art of painting, but was early led to apply later followers, particularly Sextus Emhimself to philosophy by the writings of piricus, that we learn the principles of his Democritus. He accompanied his master, school, or rather their mode of thinking

. Anaxarchus, to India, in the train of Alex- by which they strove rather to overthrow ander the Great. During this journey, he other philosophical structures, than to became acquainted with the doctrines of build up one of their own.-A disposition the Brahmins, Gymnosophists, Magi, and to doubt is often called, from this philosoother Eastern philosophers. His doubts pher, pyrrhonism. concerning positive knowledge (or his PYRRHUS; son of Achilles and Iphige scepticisin) were strengthened as he pro- nia, whom his father, after the sacrifice ceeded in his studies, until at length he of Iphigenia, carried to Scyros, and care came to hold all knowledge useless, and Deidamia. Others say that De: considered virtue alone as valuable. In damia, daughter of Lycomedes, was la all disputes, his answer to his opponents mother. He was educated at Seyms was, “What you say may, or may not, be and remained there till after his father's true; I cannot decide ;" and he taught death, when Ulysses and Diomedes 900 in his school, that truth could not be him away, because Calchas had declaret, attained, but we must be content to sus- that without bim Troy could poi be pend our judgment on all subjects. He taken. He now received the name of spent a great part of his life in solitude, Neoptolemus, on account of his engagin: and, by abstaining from all decided opin in war so young. Homer describes her ions (éroxn) concerning moral and physical as beautiful, eloquent and fearless

. Th phenomena, he endeavored to attain a post-Homeric poets ascribe to him tbe state of tranquillity not to be affected by sacrifice of Polyxena on the tomb of his fear, joy or sorrow. He bore corporal father, the carrying off of Philoctetes frog pains with great fortitude, and no danger Lemnos, and the death of Polites and could disturb his equanimity. In dispu- Priam. Andromache and Helenus feli sa tation, he was distinguished for acuteness his share among the captives. Later & of argument and clearness of language. counts differ very much. Some say His countrymen made him high priest, he returned by land; others, by water. and exempted all philosophers from the According to some, he went to Epirus payment of taxes." Pyrrho died in the among the Molossi, and there founded : ninetieth year of his age. The Athenians new kingdom. Here Andromache be erected a statue in honor of him, and his came his wife, by whom he had Molosza countrymen raised a monument to his Pierus and Pergamus, and, at length, les memory. His scepticisin is easily ac- his wife and his kingdom to Helena counted for. He early became acquainted whom he honored as a soothsayer

. He

to

then appears in a new mythological series sors of Moschus and other priests of the of events, the basis of which is to be country, by whom he was initiated into found in Homer. He is represented to their mysteries, and that he travelled have married Hermione, whoin her father, through various parts of Syria, in order to Menelaus, had betrothed to him before become acquainted with the most imporTroy. On this account he was, according tant religious usages and doctrines. But to some, murdered by Orestes, the former this account is blended with many fabuhusband of Hermione, at the altar of lous circumstances. Pythagoras is said to Apollo. According to others, his death have been recommended by Polycrates, was occasioned by Apollo, whom he had king of Samos, to the Egyptian king offended. It is generally agreed, that his Amasis. In Egypt he was probably inideath took place at Delphi. Here his tiated into the mysteries of the priests, grave was shown, and a yearly sacrifice and became acquainted with the whole was offered in honor of him.

range of Egyptian learning. From Egypt PYRRHUS II, king of Epirus, B. C. 300, he is said to have journeyed to the East, was one of the greatest generals of his and visited the Persian and Chaldean age, ambitious of fame and conquest. He Magi, as well as the Indian Gymnosoascended the throne of his father when phists. After his return, he opened a but twelve years old : being driven from school at Samos, in which he taught his it , five years afterwards, by Neoptolemus, doctrines in a symbolic form, in imitation he soon regained it, and increased his of the Egyptians. Tradition, moreover, power by the conquest of Macedonia. relates that he went to Delos, and received Being called by the Tarentines (see Ta- from the priestess moral maxims, which rentum) to aid them against the Romans, he communicated to his disciples under he twice defeated the latter by means of the name of divine precepts. He also his elephants, to which the Romans were visited Crete, where the priests of Cybele unaccustomed; but his confession, “Such took him to the caverns of Ida, in which another victory, and I must go home Jupiter had been cradled, and where his alone," proved the cost of his triumph. grave was pretended to be shown. Here In the mean time, the disturbances in he met Epimenides, who boasted of havSyracuse tempted him into Sicily. Buting intercourse with gods and the gift of he returned to Italy, without having ac- prophecy, and wbom he initiated into the complished his vain scheme of conquest ; sacred mysteries of the Greeks. From and being here defeated by the Romans, Crete he is said to have gone to Sparta who had now become acquainted with his and Elis, and from thence to Phlius, mode of fighting, he was obliged to re- where, being asked by king Leon what turn to Greece, without having succeeded was his profession, be replied that he was in his designs. A tile, at the siege of a philosopher (or friend of wisdom), deArgos, ended his restless life (272 B. C.). claring that the name of sage (sophos) From this king the Romans learned most belonged solely to the Divinity. With of their art of war, which afterwards augmented knowledge he returned home, made them so formidable to their enemies. where he now founded a philosophical (See Fabricius.)

school with great success. His doctrines PYTHagoras; a Grecian philosopher, seemed divine oracles; and the sacred founder of the Italian school. According obscurity in which he had the art of veilto the most received opinion, he was a na- ing them, attracted a great number of distive of Samos. His father, Mnesarchus, ciples. He resolved, nevertheless, to leave was a merchant (probably of Tyre or somé Samos, either to avoid the public offices other Phænician city), who traded to Sa- conferred upon him, or the tyranny of mos, where he received the rights of citizen- Polycrates, and went to Magna Græcia. ship

, and settled with his family. The year He landed at Crotona, whose inhabitants of Pythagoras's birth is uncertain ; proba- were notorious for the looseness of their bly it took place about 584 or 566 B. C. manners. From all traditions it may be His history is mingled with many fables. concluded, that he laid claim to supernatHe received his first instruction from Cre- ural powers, and his extraordinary qualiophilus in his native city. He then went ties collected around him persons of all to the island of Scyros, and was a scholar classes. The good effects of his influence of Pherecydes till the death of the latter; were soon visible. Sobriety and temperothers make him also a scholar of Thales. ance succeeded to the prevailing luxury Jamblichus says, that Pythagoras, during and licentiousness. Six hundred of the his journey to Egypt, spent some time in inhabitants of Crotona are said to have Phænicia in intercourse with the succes- submitted to the strictest precepts of his

doctrine, and united their property in one ciety, whom he subjected to a separate common stock, for the benefit of the whole discipline, and not till after long instrucommunity

or society wbich Pythagoras tion and severe examination admitted founded. The object of the society was all the mysteries of his secret doctrines to aid each other in promoting intellectual These scholars were required to practe cultivation. From all quarters Pythago- the greatest purity and simplicity of matras found numerous pupils, who paid him ners. He imposed upon them a silence de almost divine honors. But as he taught two to five years, according to circumthe nobles, who joined him, his society stances (the Pythagorean silence). For a . became suspected by the popular party. time, the disciples were only hearers. The At the head of his enemies in Crotona well-known · He said so (aires épaja wa was Cylon, a rich and respectable citizen, sufficient authority, without any prací whose enmity he had excited by refusing He alone, who had passed through the to receive him among his scholars. In appointed series of severe trials, was al revenge, Cylon once attacked the house lowed to hear the word of the master o of Milo, where a number of Pythagoreans his immediate presence. Whoever we were assembled, surrounded it with his terrified by the difficulties, might withpartisans, and set it on fire. Forty per- draw without opposition, and his contsons perished, and but few escaped. Py: butions to the common stock were repas thagoras was probably not in the house. a tomb was erected to him as if he were He Aed to the Locrians, and, when these dead, and he was no more thought refused to receive him, to Metapontum. To the members of the secret society

, the Finding enemies here also, who meditated doctrines were not delivered, as to oilers his ruin, he sought an asylum in the tem- under the mask of images and symbals ple of the Muses, where, according to tra- but unveiled. These secrets probably edition, he perished from want of suste- lated to religious and political subjects nance, eighty years of age (about 506 B. C.). It was requisite, bowever, to take an web His scholars are said to have paid him di- of secrecy. The pupils could now inte vine hovors after his death. He is said to rogate and make objections. They were have asserted, that his soul had already called, by way of distinction, Pythogores lived in several bodies. In public he ap- As soon as his disciples had made sutipeared in the Oriental costume, in a long cient progress in geometry, they were white robe, with a flowing beard, and, as introduced to the study of nature, to the some say, with a crown of gold on his investigation of fundamental principles head. His exterior was grave, command- and to the knowledge of God. Others ing, and dignified. He abstained, it is according to their inclinations and capacrelated, from all animal food, and limited ties, were instructed in inorals, econehimself to vegetables, not, however, eating ics, or politics, and afterwards emplos beans. These circumstances contributed either in managing the affairs of the soc to give him the appearance of an extraor- ety, or sent abroad to inculcate and brisa dinary being. To show his respect for into practice the principles of philosti marriage, he took a wife at Crotona, by and government in the other Grecia whom, among several children, he had cities. According to the accounts of two sons, Telanges and Mnesarchus, who later writers, the mode of living at the were bis scholars and successors. That Pythagorean school at Crotona, was by Pythagoras left any works, is improbable following: The Pythagoreans, with the on the testimony of the ancients. The wives and children, lived together in a Golden Sentences, extant under his name, public building, in perfect harmony, a i which may be considered as a short one family. Each morning it was die abridgment of his popular doctrines, ap- cided how the day should be spent, as pear to have been composed by later every evening a review was made of 2 hands. Like those of the Egyptian priests, that had been done. They rose before his doctrines were of two kinds, public the sun, in order to worship it; verse and secret. His public instruction con- from Homer and other poets were the sisted of practical discourses, in which he recited, or music was introduced, to aros recommended virtue and dissuaded from the mental powers, and fit them for the vice, with a particular reference to the duties of the day. Several hours we various relations of mankind, such as then spent in serious study. A pause those of husbands and wives, parents and followed for recreation, in which a solitar children, citizens and magistrates, &c. walk was usually taken, to indulge ! His hearers at these lectures must not be contemplation; a conversation then took confounded with the members of his so- place. Before dinner, various gymnasi

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