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CCLOPH'ONT, the dark-coloured resin 

 which remains in the retort after distil- 

 ling rough turpentine without water, 

 named thus from Colophon, a city of 

 Ionia, whence it was first brought. 



CoLoauix'TiDA. See COLOCYNTH. 



CO'LOR (Latin), a property of bodies by 

 which they separate the elementary rays 

 of light, and absorb some and reflect 

 others. Thus the colours of the spectrum 

 are red, orange, yellow, green, blue, in- 

 digo, and violet ; and any body which ap- 

 pears to possess any of these colours, has 

 simply the property of absorbing all the 

 rays of the spectrum except that one, 

 which it reflects. The primary colours 

 are red, yellow, and blue; all others may 

 be produced by combinations of these. 



COL'UBER (Latin), a serpent ; a genus of 

 venomous serpents with isolated fangs. 



COLUM'BA, No A/CHI (Xoah's Dove}; one 

 of the new constellations situated imme- 

 diately below Lepus. 



CQLUM'BIC ACID, the peroxide of Colum- 

 bitun, evincing acid properties. It is a 

 white powder. 



COLCM'BIA, a bitter crystalline princi- 

 ple, obtained from Columbo root. 



COLCMBIOM, from Columbia, America, a 

 metal discovered by Mr. Hatchett in 1801, 

 in a mineral brought from North Ame- 

 rica. It is also called Tantalium, from 

 the mineral tantalite found in Sweden. 



COLUMEO RI.-OT, the root of the Cocctihis 

 pnlinatus, which grows in the forests of 

 Mozambique, where it is named kalumb ; 

 the Portuguese import it under the name 

 of Raiz de Columba. The root is peren- 

 nial, and is used as an antiseptic and 

 tonic. 



COL'UMEL, Lat. columella, a column' or 

 little pillar, as that which unites the 

 partitions of the capsule of a plant, or 

 that in the centre of most univalve shells. 



COL'CMS, Lat. columna, a prop. In ar- 

 chitecture, a round pillar, the parts of 

 which are the base, on which it rests, its 

 body called the shaft, and the head called 

 the capital. The capital finishes with an 

 abacus, and the base is supported on a 

 plinth. The shaft is in general either 

 plain or fluted, but carolytic columns have 

 foliated shafts. Columns are moreover 

 distinguished as to their form into Tus- 

 can, Doric, Ionic, Corinthian, and Com- 

 posite. 



COLL-M'SCLA (Latin), a little column; 

 the name of the filament which passes 

 through the middle of the capsule of 

 frondose mosses, to which the seeds are 

 connected. 



CO'LURE, from %o).o{, mutilated, and 

 oue/x,, a tail ; a name common to two great 

 circles of the sphere, supposed to inter- 

 sect each other at right angles in the 

 poles of the world , one of them passing 



through the solstitial, and the other 

 through the equinoctial point of the 

 ecliptic, thereby dividing the ecliptic 

 into four equal parts. The points where 

 these lines cut the ecliptic are called car- 

 dinal points. The colures take their name 

 from a part being always below the hori- 

 zon. 



COLYM'BUS, a genus of birds of the Pal- 

 mipede order, comprehending the Divers, 

 Grebes, and Guillemots. Name from 

 x.o\vua.(u, to swim. 



COL'ZA, a variety of the cabbage plant, 

 the Srassica oleracea, whose seeds afford 

 by pressure an oil much used on the 

 continent for burning in lamps and other 

 purposes. 



CO'MA. 1. In medicine, a morbid state 

 resembling sound sleep, produced by com- 

 pression of the brain and various other 



causes; from x[6at, sound sleep. '2. In 



botany, a comb or fascicle of leaves on the 

 top of a stem or stipe, from XO/JMI, hair. 



CO'MA BEREXI'CES (Berenices hair), an 

 asterism situated north by Canis vena- 

 tici, east by Bo&tes, south by Leo and 

 Virgo, and west by Leo and Ursa Major, 

 43 stars. 



COMBE. The term combe is usually ap- 

 plied to that unwatered portion of a val- 

 ley, which forms its continuation beyond 

 and above the most elevated spring that 

 issues into it ; at this point or spring-head 

 the valley ends and the combe begins. 



COMBINA'TIOX, from com and bimm, two 

 and two. 1: In chemistry, the intimate 

 union resulting from the action of that 

 species of attraction which we call affi- 

 nity. See AFFINITY. 2. In mathema- 

 tics, the variations which may be made 

 in the arrangement of any given number 

 of things in groups, are called combina- 

 tions. Thus the combinations or differ- 

 ent ways in which five articles may be 

 arranged or combined are 120, and are 

 found by multiplying together the terms 

 1,2,3,4,5=120. 3. In law, combina- 

 tion may take place for the performance 

 of an unlawful act, and is punishable be- 

 fore such act is done. 



CoMBOs'TiBLE,a body which, in its rapid 

 union with others, causes disengagement 

 of light and heat. The simple combus- 

 tibles are sulphur, phosphorus, carbon, 

 hydrogen, all the metals, and boron. 



COM'ET, from coma, hair ; an opaque, 

 spherical body like a planet, performing 

 revolutions about the sun in an elliptical 

 orbit, having the sun in one of the foci. 

 In popular language comets are tailed, 

 bearded, or hairy, these terms being taken 

 from the appearance of the light which 

 attends them. In their different posi- 

 tions with respect to the sun, the body 

 appears to have a tail or train, a beard, 

 or to be bounded by a fringe of light. 



