Page:The American Cyclopædia (1879) Volume I.djvu/495

 ANATOMY, COMPARATIVE ANAXIMENES 463 the elementary organic parts of nearly every tissue, and that all chemical changes occur in them, as integral elements of structure, with- out altering their numbers and relative posi- tions ; that these minute anatomical elements, in fact, are as permanent in form as the tissues and the organs they compose ; and that all growth in the individual organism takes place by a relative enlargement of their size, and not by any increase of their number ; so that, as the organs remain the same in form and num- ber hi the adult as in the new-born child, the same is true of the tissues that compose the organs, and the microscopic cells composing tissues. The principal varieties of cells now recognized are : the red globules of the blood, flattened, circular bodies, homogeneous in structure, from 3-^5- to ^^ of an inch in diameter; the white globules of the blood, which are colorless and granular, spherical in form, and 2 S 1 6 of an inch in diameter ; scale- like epithelial and epidermic cells, very thin, pentagonal or hexagonal in shape, with a round or oval nucleus imbedded in their substance ; columnar and ciliated epithelium cells, lining certain parts of the alimentary canal, air pas- sages, generative organs, and ventricles of the brain ; glandular epithelium cells, forming the active agents of secretion in the glandular organs ; and the nerve cells of the brain, spinal cord, and ganglia. The fibres are : the white fibres of areolar tissue, of tendons, fasciae, and the like ; the yellow elastic fibres of elastic tissue; the compound muscular fibres; and ultimate nervous filaments. The tubular ele- ments are the capillary blood vessels and lym- phatics, and the straight or convoluted tubules of the kidneys, the testicles, and some of the glandular organs. The homogeneous or granu- lar substratum, in which these anatomical elements are imbedded, varies in consistency and composition in the different tissues. ANATOMY, Comparative. See COMPAEATIVE ANATOMY. AXAXAGORAS, a Grecian philosopher, born at Clazomenro in Ionia, about 600 B. 0., died in 428. He rejected wealth and honors that he might indulge his love of meditation and phi- losophy. From Clazomense he removed to Athens, where he lived in the closest intimacy with Pericles, and also numbered among his friends or pupils several of the most distin- guished Athenians of that period. Anaxagoras is generally considered the first of the Greeks who conceived of God as a Divine Mind (by him termed vovg) acting upon matter with con- scious intelligence and design. He taught that the sun was no deity, but an inanimate fiery mass, and therefore not a proper object of wor- ship ; and that the miraculous appearances at sacrifices were explicable by natural laws. He suggested that the moon shone by reflected light, and rightly explained solar and lunar eclipses. His attempt to account for these phenomena, at that time regarded as super- natural, on natural principles, brought him into great danger. He gave moral expositions of the myths of Homer, and explained the names of the gods by allegory. As a penalty for what was accounted his impiety, he was con- demned to die ; but through the influence of Pericles his sentence was commuted to banish- ment. He retired to Lampsacus, on the Hel- lespont, and died there a few years later in poverty. A little before his death the senate of Lampsacus sent messengers to inquire what commemoration would be most acceptable to him ; he answered, " Let all the boys have a play day on the anniversary of my death ! " This festival was called Anaxagoreia, and was observed for centuries.. The fragments of his works have been collected by Schaubach (Leip- sic, 1827), andbySchorn (Bonn, 1829). A .VAX AIU'II I'S, a Grecian philosopher, a native of Abdera in Thrace, who attended Alexander the Great into Asia, and succeeded in winning his friendship by his wit and servility. After the death of Alexander, in 323 B. C., Anaxar- chus, while returning to Greece, is said to have been shipwrecked on the coast of Cyprus, and pounded to death in a mortar by order of Ni- cocreon, one of the princes of that island, whom he had offended. AXAXIMANDER, a Grecian philosopher of the Ionian school, born at Miletus in 610, died about 547 B. C. He is said to have led a colony to Apollonia in Illyria, and many won- derful deeds and inventions are ascribed to him. Grecian philosophy is indebted to him for the word apxr), signifying origin or prin- ciple. His general doctrine, as stated by an- cient writers, concerning the origin of nature, was that the first principle of all things is in- finity (TO aireipov) ; that the universe, though variable in its parts, as a whole is fixed and unchangeable ; that infinity is the beginning and end of all things. He was the first to commit philosophical doctrines to writing. He wrote a treatise on geometry, and made calculations on the distances and size of the heavenly bod- ies. He held that the stars are globes of air and fire animated by divinity, that the earth is a globe fixed in the centre of the universe, and that the sun is 28 times as large as the earth. He was the first to compose a trea- tise on geography, and also prepared a chart of such portions of land and sea as he was acquainted with. According to some, he in- vented the sun dial. ANAXIMENES. I. A Grecian philosopher, born at Miletus, flourished in the latter half of the 6th century B. C. He taught that the essence of all things is air, whence all things are produced by condensation and rarefaction through eternally existing motion; that the sun and moon are fiery bodies of a flat, circu- lar form; that the stars are also fiery sub- stances, fastened like nails in a crystalline sphere ; and that the earth is a tablet resting on air. II. A native of Lampsacus, a historian and ^ rhetorician, and one of the preceptors of Alexander the Great. He wrote a history of