Page:The New International Encyclopædia 1st ed. v. 04.djvu/536

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CHAISSAIGNAC.
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CHALCEDONY.

CHAISSAIGNAC, shâ'sâ'nyâk', Charles Marie Edouad (1805-79). A French physician He was born in Nantes, and in 1835 became pro-sector and professor at the university and physician at the Central Bureau of the Hospitals of Paris. He is the originator of the surgical operation known as écrasment, by means of which tumors, piles, polyps, and other growths may be removed without the effusion of blood. The general introduction of drainage in surgery is also due to his initiative. His principal works include: Traité de l'écrasment lineaire (1856); Lecons sur la trachéometrie (1855): Clinique chirugricale (1854-58); Traité pratique de la suppuration et du drainage chirurgical (2 vols., 1859) ; Des l'emnpnisonnement du sung par matiéres organiques (1873).

CHAIX D'EST ANGE, shä'dâ'tänzh', Gustave Louis Addolphie Victor Charles (1800- 70). A French advocate and politician. In 1857 Napoleon III. appointed him procureur genéral and soon after Councilor of State. In 1862 he was made Senator. In 1863 he was vice-president of the Council of State; and in 1864 was appointed president of the Department of Public Works and Fine Arts. As an advocate, especial- ly in criminal cases, be won great fame.

CHAJ'JUG. Sec Hayyuj.

CHALAZA, ká-lā'za (Neo-Lat., from Gk. χάλαζα, chalaza, hailstone, pimple). The basal region of an ovule, in which there is no differentiation of integument. See Ovule.

CHALAZOGAMY, kăl'a-zŏg'ă-mĭ (from Gk. χάλαζα, chalza, hailstone, pimple + γάμος, gamos, marriage, from γαμεῖν. gamein, to marry). The passage of the pollen-tube through the chalaza of the ovule. In seed-plants the pollen-tulie ordinarily reaches the egg by passing through

Casarina showing chalazognamy: p. pollen-tube descending to the chalazal region of the ovule and entering the bundle-region (b), turning upward into the nucellus (n), entering the embryo-sac (e) from below, and thus approaching the egg.

the micropyle. which is a small passageway left by the integument of the ovule. In certain eases, however, it has been discovered that the pollen- tube does not enter in this way, but pierces the ovule in the general region of the chalaza whch is the base of the ovule, where the integument and body of the ovule are indistinguislialde. In this way the tube approaches the egg from beneath, and burrows its way through the intervening tissue. This phenomenon is known as 'chalazogamy,' as distinguished from the ordinary method, which has been called 'porogamy.' Chalazogamy has been discovered as yet only in connection with the amentaceous trees, those in which it has been recorded being birch, alder, hornbeam, walnut, hazel, casuarina, and elm. While in most of these cases the pollen-tube enters through the chalazal region, in the elm it passes into the ovule above the chalaza. However, the term chalazogamy has been extwnded to include all cases in which the pollen-tube does not enter by way of the micropyle.

CHALCE'DON (Lat., from Καλχηδών, Kalchēdōn, or Χαλκηδών, Chalkēdōn). A city of ancient Biithynia, at the entrance of the Bosporus, opposite to Byzantium. It was founded about B.C. 677 by a colony from Megara, and soon became a place of considerable trade and importance. It contained several temples, one of which, dedicated to Apollo, had an oracle. After the liberation of the Greek cities from Persian rule, Chalcedon joined the Athenian League, but at the end of the Peloponnesian war came into possession of the Spartans. With the rest of Bithynia. it was bequeathed to the Romans by King Nicomedes. During the Mithridatic war it was the scene of a bold exploit of the Pontic sovereign. Bithynia having been invaded by Mithridates, all the wealthy Romans in the district fled for refuge to Chalcedon. whereupon he broke the chains that protected the port, burned four ships, and towed away the remaining sixty. Under the Empire Chalcedon was made a free city, and it was the scene of a general council, held A.D. 451. Chosroës II., King of Persia, captured it A.D. 616. after which it declined, until it was finally demolished by the Turks, who used its ruins to build mosques and other edifices in Constantinople. Chalcedon was the birthplace of the philosopher Xenocrates.

The Council of Chalcedon, to which allusion has been made, was the fourth general council, and was assembled by the Emiperor Marcian for the purpose of drawing up a form of doctrine in regard to the nature of Christ, which should equally avoid the errors of the Nestorians (q.v.) and those of the Monphysites (q. v.). Six hundred bishops, almost all of the Eastern or Greek Church, were present. The doctrine declared to be orthodox was that in Christ there were two natures, which could not be intermixed (this clause was directed against the Monophysites), and which also were not in entire separation (this was directed against the Nestorians). but which were so conjoined that their union destroyed neither the peculiarity of each nature nor the oneness of Christ's person.

CHALCEDONY, kălsĕd'ô-nĭ (Lat. chalcedonius, a gem named after Gk. Χαλκηδών, Chalkēdōn, a city in Asia Minor, where it abounded. Gk. χαλκηδών, chalkēdōn, chalcedony). A crystalline variety of quartz of various shades of white, yellow, brown. green, and blue. It is transparent or translucent, and some of the milk-white varieties are opaque. It occurs in mammillary, botryoidal, and stalactitic shapes, and as a lining