voted his time to writing on various subjects, as shown in the "Biographie Générale," Vol. XLIII. pp. 446-450. Of the works cited in latter, should be extracted, as best known: "In Aristotelis. . . de plantis," 1556; "In Theophrasti, de causis plantarum," 1566; "De Subtilitate ad Cardanum," 1557, 1560, 1576, 1592, 1634.

It is to the last-named important work that Gilbert frequently alludes (De Magnete, Book I. chaps. i. xvi; Book II. chaps. i. iii. iv. xxxviii.; Book iv. chap. i.). He says, more particularly, that Scaliger strays far from truth when, in treating of magnetic bodies, he speaks of diamond attracting iron, also that he keeps the loadstone and iron in bran to protect them from the injurious action of the atmosphere, and that Scaliger, in order to explain the difference of variation for change of locality, brings in a celestial cause to himself unknown, and terrestrial loadstones that have nowhere. been discovered; and seeks the cause not in the siderite mountains," but in that force which formed them, to wit, in the part of the heaven which overhangs that northern point.

REFERENCES.—Teissier (H. A.), "Eloges des hommes illustres "; Coupé (Jean Marie Louis), Soirées littéraires,' Vol. XV; Nicéron (Jean Pierre), Mémoires," XXIII; Larousse, Dict. Univ.," Vol. VIII. pp. 692–693.

Silvaticus-Sylvaticus-Matthæus Moretus, well-known Italian savant living in 1344, physician to the King of Naples, one of the professors at Salerno,1 and author of "Matth. Silvatici, medic. de Salerno, Liber cibalis et Medicinalis Pandectarum . . ." originally published at Naples, 1474. This work, dedicated to Ferdinand, King of Sicily, is an Encyclopædic Dictionary and one of the most important books we have of the history of medicine in the Middle Ages, and at beginning of the Italian Renaissance. The citations made by Græsse (" Trésor," Vol. VI. p. 406), state that Silvaticus was the owner of a private botanical garden at Salerno (Chap. CXCVII. s.v. "Colcasia" of the Opus Pandectarum), and allude to Thos. Frognall Dibdin's "Bibliotheca Spenceriana," Vol. IV. London, 1815, pp. 24-25, and Van der Meersch, "Rech. sur les impr. Belges," etc., Vol. I. pp. 384, etc.

66

1 The School of Salerno and the introduction of Arabian sciences into Italy are discussed with learning and judgment by Muratori (Lodovico Antonio), "Antiquitates Italia Medii Aevi.," Vol. III. pp. 932-940, and by Giannone (Pietro), Istoria Civile del Regno di Napoli," Vol. II. pp. 119127). Consult, likewise, for the Salerno school, Universities of Europe in the Middle Ages," by Hastings Rashdall, Oxford, 1895, Chap. III. pp. 75-86, and also pp. 306–307, Vol. IV. part i. of the "History of the City of Rome in the Middle Ages..." of Ferdinand Gregorovius, tr. by Annie Hamilton, London, 1896.

REFERENCES.- Repertoire et sources historiques du Moyen Age," par l'abbé Ulysse, Joseph Chevalier, Paris, 1877-1886, p. 2089; Argellati (Philippo), Bibliotheca Mediolan.," 1745; Tiraboschi (Girolamo), Storia della Letteratura Italiana,' 1807, Vol. I. p. 275; Sbaralea (Joannes Hyacinthus), "Supplementum Scriptores ordinis," 1806, P. 529; Tafuri (Giovanni Bernardino), "Scrittori Scrittori. . . di Napoli,' 1749, Vol. II. pp. 67–70; Thesaur. Lit. Bot.," 1851, p. 185; Brunet (Jacques Charles), "Manuel du Libraire," 1864, Vol. V. pp. 387-388; Watt (Rob.), Bibliotheca Britannica,' Edinburgh, 1824, Vol. II. p. 856 h; Larousse, Dict. Univ.," Vol. XIV. p. 1308; Paul Lacroix, Science and Literature of the Middle Ages," p. 117; Ludovico Hain, Repertorium Bibliographicorum," Vol. II. part ii. Nos. 15192-15202, PP. 375-376; Gilbert, De Magnete, Book I. chap. i.

Solinus, CAIUS JULIUS-Grammaticus-a Roman writer who lived in latter part of the second century, the author of a compilation in fifty-seven chapters which contains a sketch of the world as it was known to him, but which is supposed to have been taken entirely from Pliny's "Natural History." It was originally published under the title of " Collectanea rerum mirabilium," the second edition being headed "Polyhistor." This was one of the earliest known printed books, having first appeared at Venice in 1473, and it has since been translated into many foreign languages, notably during 1600, 1603, and 1847.

The most important of the three references Gilbert makes to Solinus is found in De Magnete, Book II. chap. xxxviii., where it is said that Pliny and Julius Solinus tell of the stone cathochites, affirming that it attracts flesh and that it holds one's hand, as loadstone holds iron and amber holds chaff. But that, says he, is due solely to its viscosity and its natural glutinousness, for it adheres most readily to a warm hand.

"

REFERENCES.-Dodwell (Henry, the elder), Dissertationes Cyprianica"; Moller (D. W.); C. J. Solino, in " Biog. Gén.," Vol. XLIV. PP. 153-154; La Grande Encycl.," Vol. XXX. p. 232.

"

Thebit Ben-Kora-Thabit Ibn Corrah-Abū Thabit Ibn Kurrah -Tebioth ben Choreżen (Houzeau, No. 1130), one of the most brilliant and accomplished scholars produced by the Arabs (836– 901), called by Delambre "Le Ronsard de l'Astronomie," is the author of many treatises on mathematics, and on other scientific subjects, the mention of the titles of which take up nearly two folio pages of Casiri's "Catalogue." Especially is he shown in latter as having translated into Arabic the chief works of Archimedes, Apollonius, Euclid and Ptolemy also the Physics and Analytics of Aristotle and many of the works of Hippocrates and Galen.

Incidentally it may be added that geometry, to which Thebit Ben-Kora gave particular attention, was named by the Arabs handassah, and that the Tahrir Hendassiat contains: the explication,

the data and the optics, of Euclid, the syntaxis magna of Ptolemy, the spherics of Theodosius and his book concerning night and day, the spherics of Menelaus, the movable sphere of Autolycus, the ascendants or horoscopes of Asclepius, a treatise of Aristarchus on the discs of the sun and moon, the lemmas or theorems of Archimedes, also his treatise on the sphere and cylinder, the conics of Apollonius and Thebit Ben-Kora, a treatise of Theodosius on the positions, or quiescence, of bodies, etc., etc. (D'Herbelot, art. Handassah, and Aklides. See also, for origin of geometry, etc. "A Short History of Greek Mathem.," Jas. Gow, Cambridge, 1884, pp. 123–134.)

The allusions by Gilbert are to be found, Book III. chap. i., and Book VI. chap. ix. of De Magnete, in which latter it is said that, Thebitius, in order to establish a law for the great inequalities in the movements of the stars, held that the eighth sphere does not advance by continued motion from west to east, but that it has a sort of tremulous motion, "a movement of trepidation."

"

REFERENCES.-"Hist. de la Médecine Arabe," par Dr. Lucien Leclerc, Paris, 1876, Vol. I. pp. 168-172; Dreyer (J.), "Tycho Brahe," 1890, pp. 354-356; Houzeau et Lancaster, Bibl. Gén.," Vol. I. part i. pp. 466-467, 702; History of Mathematics," Walter W. Rouse Ball, London, 1888, p. 153; Abhandlungen zur Geschichte der Mathematik," Vol. VI, Leipzig, 1892, pp. 25-26.

"

Themistius of Paphlagonia-surnamed Euphrades—was a distinguished Greek orator and writer (about 315-390), whose philosophical works consist of commentaries in the form of paraphrases on some of Aristotle's writings, one being upon the work “On Heaven," and the other upon the twelfth book of the "Metaphysics." The paraphrases were first published by Hermolaus Barbarus in 1481. Gilbert's only reference is briefly made in De Magnete, Book II. chap. iv.

REFERENCES.-Schöll (Carl), pp. 96, 388, or Hist. de la Litt.

"

Geschichte d. G. Litt.," Vol. III. Grecque," Vol. VI. p. 141; Vol. VII. p. 121; Photius, cod. LXXIV; Fleury, Hist. Eccles."; Tillemont, Hist. des Emp.," Vols. IV and V; Šuidas, art. Themistius"; E. Baret, De Themistio sophista . . . Paris, 1853; Brucker, "Hist. Crit. de la Phil.," Vol. II. p. 484.

"

Zoroaster-Zarath 'ustra-Zerdusht-founder of the religious system contained in the Zend-Avesta (religious book of the Parsees, fire worshippers), is said to have been a native of Bactria, near the modern Balkh, and to have lived about 589-513 B.C. That he was an historical personage, equally with Buddha, Confucius and Mahomet, it is now scarcely possible to doubt.

His able biographer in the English Cyclopædia, London, 1868, Vol. VI. pp. 946–948, states that Zoroaster was a great astrologer and magician, and it is said at p. 95 of Mr. A. V. W. Jackson's

admirable work on Zoroaster, published in New York, 1899, that some of the original Nasks of the Avesta are reported to have been wholly scientific in their contents, and that the Greeks even speak of books purported to be by Zoroaster treating of physics, of the stars and of precious stones.

Zoroaster is merely named by Gilbert in manner shown at the Hermes Trismegistus entry.

"

REFERENCES.—“ Life of Zoroaster," prefixed to Anquetil du Perron's Zend-Avesta," Paris, 1771; Pastoret (Claude Emmanuel J. P. de), Zoroaster, Confucius et Mahomet comparés," 1787; Hyde (Thomas), Historia ... Veterum Persarum Oxford, 1760; 'ZendAvesta, Ouvrage de Zoroastre," 2 vols. Paris, 1771; Martin-Haug (I.), "Essays," Bombay, 1862; Malcolm (Sir John), History of Persia," 1815; Darmesteter, "Ormazd et Ahriman," Paris, 1877; Spiegel (Friedrich), "Erânische Alterthumskunde," Leipzig, 1871-1878; Chas. Rollin, Ancient History," London, 1845, Vol. I. PP. 234-235, 237; Ritter (Dr. Heinrich), "History of Ancient Philosophy," London, 1846, Vol. I. p. 52; "History of the Decline and Fall of the Roman Empire," Edward Gibbon (Milman), Philad., 1880, Vol. I. pp. 229-230, notes, and, for abridgment of his theology, pp. 231-234; also the Bury ed., London, 1900, Vol. I. pp. 197-198, 456-457; Vol. V. p. 487; Classical Studies in Honour of Hy. Drisler," New York, 1894, PP. 24-51; "The Fragments of the Persika of Ktesias," by John Gilmore, London, 1888, pp. 29-36, 95; 'The Great Monarchies of the Ancient Western World," by Geo. Rawlinson, London, 1865, Vol. I. p. 195; Vol. III. pp. 93, 98, 105, 127, 135-139, 164; Vol. IV. pp. 110, 333; "Essai Historique," Eug. Salverte, Paris, 1824, Vol. II. p. 503.

To the foregoing "Accounts of Early Writers," can properly be added the following happy description of "The School of Athens." 1 as coloured by Raphael and now to be seen among his frescoes in the papal state-apartments (Stanze-Camere) of the Vatican in Rome, for, it will be observed, most of the leading writers of which we have spoken are therein depicted :

"The School of Athens "-Scuola d'Atene-represents Philosophy in general, and is, with regard to expression and scholastic knowledge, a wonderful work; for every philosopher, by his posture and gestures, characterises his doctrines and opinions. . . . Beginning with the Ionian School, on the right, before the statue of Minerva, the aged person whose head is covered with linen, after the Egyptian manner is Thales; whom Raphael has represented as walking with a Stick, because, with that, he measured the Pyramids. Next to Thales is Archelaus of Messenia. . . . Behind them is Anaxagoras, resting his foot upon a marble book and almost hidden; in reference to the persecutions he underwent. The next figure, standing alone, at a little distance, to show that he is of another School, represents Pythagoras; who seems resolved to continue fixed at one spot, to

1 Extracted from " Information and Directions for Travellers," by Mariana Starke, 8th ed., John Murray, London, 1832.

show the unchangeableness of his ideas . . . his head and body being turned different ways shows his metaphorical method of teaching important truths; and the crown, formed by his hair, refers to his initiation in all mysteries. The Figure leaning on a column is Parmenides; close to whom sits a youth, his adopted son Zeno, who is writing something short; referring to a Poem, by Parmenides, which compared, in two hundred lines, all the various Systems of Philosophy. Two masters only of the Eleatic School are introduced; because its followers were few in number. The metaphysics of Parmenides and Zeno gave rise to the Sceptical Philosophy of Pyrrho, expressed by the next figure. . . . At the opposite side of the Picture, talking with his fingers to a Figure in armour, supposed to represent Alcibiades, is Socrates . . . who, like Thales, appears to be walking; because geometry was never taught in a fixed place. . . . Plato and Aristotle are placed together on a flight of steps in the centre of the Picture Plato, representative of the speculative school, holds the Timæus his sublime style is expressed by his attitude, denoting that his thoughts soar above this earth; and the cord attached to his neck marks his initiation at the Eleusinian Mysteries. . . . Aristotle, founder of ethical and physical philosophy, points earthward. The Figure in shade, nearest to Plato, is Archothæa. . . . The next Figure, in the same line, indicates roughness of character, and represents Xenocrates. . . . Behind Socrates and another Figure, Lasthenia, is a bearded old man Zeno of Citium, the founder of the sect called Stoics. . . . Behind Zeno of Citium is Antisthenes, in shade, because his School is expressed by that of Zeno. On the side of Aristotle, the tallest and most conspicuous Figure is Theophrastus . . . said to be the portrait of Cardinal Bembo. The next figures are Strato of Lampsacus, Demetrius Phalereus, Callisthenes, Neophron, Glycon. Behind the last named is Heraclides and in rear of the disciples of Aristotle are Euclid of Megara and Eubulides of Miletus, his pupil: the last hated Aristotle, and is looking angrily at him. The lower part of the Picture, on the side with the statue of Apollo, represents the Philosophy of Leucippus, the disciple of Zeno, though the author of a very opposite system. He first taught the doctrine of Atoms. Democritus, his most celebrated disciple, is sitting near him-booted, in the manner of his countrymen, the Abderites-and writing upon a stone table, shaped like the sacrophagi among which he used to meditate he lost his fortune, therefore his dress indicates poverty; and he is represented in deep meditation, to show his uncommon studiousness. Opposite to Leucippus sits Empedocles, resting on a cube, though not with contempt, according to the principles of Leucippus; because Empe