COLONY. 165 COLOR. power departed. By its victory over Spain in 18!I8, the United States took its place among the colonial powers of the world; and through the solution of the problems pre.senled liy the necessity of reconciling the element of autocracy inherent in the administration of foreign posses- sions with the republican theory of Anieriean institutions, the term colony, already loose in meaning, has attained a still broader applica- tion. See the articles on the various countries for detailed accounts of their colonies. BiBLiOGR.vpiiT. Brougham, A n Inquiry into the Cohiiiial Policy of the European Powers (Edinburgh, 1803); Heeren, A Manual of the llintory uf the Political System of Europe (Lon- don, 1S57) : IMoney, Java, or How to Manage a Colony (London, 1801); Cairnes, Colonization ond Colonial Oocernmcnt (London, 1873); Le- roy-Beaulieu. Dc lu colonisation chcz Ics pen pics moderncs (Paris, 1874) ; Deekert, Die Kolonial- reichc und Kolonisationsohjckle dcr ilegenwart (Leipzig, 1885) ; Roscher, Kolonien, Kolonial- polililc iind Ausu-anderuny (Leipzig, 1885) ; Payne, History of European Colonics (London, 1880) ; Xorman, The Peoples and Polities of the Far East (London, 1893) ; Worsfold, South Af- rica: A Study in Colonial Administration, and Development (London. 18!)5) ; Dubois. Syslimcs coloniaiix et peuplcs crjlonisalcurs (Paris, 1805) ; Englehardt. Les proieetorats aneicns et nio- derncs (Paris, 1800); Zimmermann, Die euro- piiisehen Kolonien (Berlin, 1896-1001) ; Lanes- san, Principes de colonisation (Paris, 1897); Kidd, The Control of the Tropics (London, 1898) ; Reinsch, World Politics (New York, 1900). and Colonial Clovernment (New York, 1902): Giddings, Demoeraci/ and Empire (New York, 1900) : Dilke, The British Empire (Lon- don, 1809) ; Egerton. .1 Short History of British Colonial Policy (London, 1897); Gaflfarel, Lcs colonics franfaises (Paris, 1893) ; Lanessan, L'expansion eoloniale de la France (Paris, 1880); Franzel, Deutschlnnds Kolonien (Han- over, 1889). COL'OPHON (Lat.. from Gk. KoXo^ciy, 7vo/o- phon ) . An ancient Greek city of Ionia in Asia ]Minor. It was situated on the river Hales, about nine miles north of Ephesus, was the native city of ilimnermus. and claimed to be the birth])lace of Homer. The expression, 'to put the Colophon,' meaning 'to give the finishing stroke.' is ex- plained by Strabo as arising from the belief that the cavalry of Colophon was so excellent that it always decided the contest. Hence, Colo- phon of a device at the end of a book. COL'OQUIN'TIDA. See Colocyntii. COLOR (Lat.. connected with Lat. cclare, Gk. KaXtiirreij/, l-alyptein, Ger. hchlcn, to hide. Ir. crliiii. I conceal. Skt. sarana. refuge). The color of an object in nature depends upon sev- eral conditions: the character of the light which illuminates it. the phenomena which take ]dace in the body itsMf. the individual ]ieculiarities of the eye Avhich views the body. It has been shown by Sir Isaac Newton that ordinary white light may be regarded as a mixture of many colors: that is. it may be analyzed into jiarts, each part producing a different color-sensation. In scientitie language, the sensation wliite. as perceived by looking at any ordinary 'white' ob- ject, is due to the incidence upon the eye of trains of ether-waves of different wave-numbers. varying continuously between certain limits; while, if a train of waves of a definite wave- number enters the eye, the .sensation of color (if any) will be of a dctinile hue. Thus we speak of yellow light, of led light, etc., meaning those ether-waves which produce these si'nsa- tions of yellow or red in a normal eye. When the ether-waves fall upon an ol)ject, some of the energy goes into relleeted waves at the surface. the rest goes into the entering waves; there will in general be absorption in the interior; but it the body is transparent there will be trans- mitted waves, and also, in general, waves re- lleeted and scattered by little particles in the interior of the body. The color of a green leaf is due to the fact that when viewed in ordinary daylight, out of all the waves which enter the leaf, only those which combine to produce the sensation green are transmitted, the others being absorbed by the coloring matter of the leaf; thus, those waves which are scattered by the minute interior parts traverse a layer of this coloring matter, and only green light emerges from ail sides. The light which in this ease is reflected at the surface is simply diffuse white light. An object whose color is due, as here, to what is called 'body absorption,' appears of the same color when viewed by retlected light or by transmitted; that is, if we look through it at the source of light, or look at it from the same side as is the source. The colors of almost all natural objects are due to this body absorp- tion. The colors of metals, however, and some ani- line dyes, are due to what is called 'surface ab- sorption.' When wliite light is incident upon a piece of gold, yellow light is reflected by the surface, thus giving the yellow color. If, how- ever, the gold is hammered out e.xceedingly tliin, it will be found to transmit greenish-blue light; so that in the case of surface color, the colors by reflection and transmission are different. The energy of the waves which are absorbed in bodies generally goes to producing heat effects; but in some cases it is spent in producing other ether-waves, thus giving rise to other colors. These bodies are called 'fluorescent.' (See Fluorescence.) In these cases, then, the color as seen by transmission and by looking at the bodies sidewise will be different. The color of the blue sky, of fine smoke, and of water in many lakes is due to the scattering of light by extremely small partides — generally minute solid particles ; for the short waves — that is. blue light — are reflected by minute par- ticles, wliile the other waves simidy pass around them. In all these cases it is evident th;it if the incident light is altered, so will be the color perceived. A green leaf in a yellow light w'ould appear black. For an excellent treatise on color, consult Rood, Modern Chromatics (New York, 1879). See Light. COLOR. In art. either the pigment employed to iH'oduce a certain effect to the eye, or the effect tlius produced — i.e. the tint of a picture. In the former sense it is treated of in this work under the names of the colors themselves. In the latter sense it may be defined as the gen- . eral effect of all hues entering into the composi- tion of the picture. The .sensation of color is produced by waves of light setting into vibration fibres of the optic nerve, and the length of these light-waves is
