C II R 



C I R 



or any discrimination, to a great variety 

 of precious stones, till Werner defined it 

 accurately, and confined it to that stone 

 which the French mineralogists distin- 

 guish by the appellation of Peridot (sorte 

 de pierre precieuse, peu recherchee, qui 

 tire un peu sur le vert.) Chrysolite 

 contains a very large proportion of mag- 

 nesia, according to some authorities more 

 than half its weight, but agreeably to the 

 analysis of others from forty to fifty per 

 cent. Chrysolite is of a green colour, 

 inclining to yellow ; its texture is foli- 

 ated ; fracture conchoidal. It causes 

 double refraction. It is infusible at 150, 

 but at that temperatue loses its transpa- 

 rency, and becomes of a dark grey. With 

 borax it melts, without effervescence, into 

 a transparent glass of a light green 

 colour. The chrysolites of commerce^ 

 come from Upper Egypt and the Brazils ; 

 they are also found in Ceylon, in South 

 America, and in Bohemia. The variety 

 called Olivine is met with in Scotland ; 

 of this the colour is olive-green. Accord- 

 ing to the analysis of Klaproth, chrysolite 

 consists of magnesia 43.5, silica 38'5, 

 oxide of iron 19. 



CHRY'SOPRASE. (from xpvaoQ, gold, and 

 prasinus, green ; ckrysoprase, Fr. Pierre 

 precieuse d'un vert clair mele d'ttne 

 nuance de jaune.} A precious stone of 

 an apple-green colour. It is a variety of 

 quartz, or of calcedony. It owes its 

 colour to the presence of the metals 

 nickel and iron, in small quantities. It 

 is found in different parts of Germany, 

 particularly in Silesia. It is always amor- 

 phous, and possesses but little lustre. It 

 consists of 96 per cent, silica, 1 per cent, 

 oxide of nickel, with a trace of iron, 

 alumina, and lime. 



CI'CATRICE. i (cicatrix, Lat. cicatrix, Fr. 



CICA'TRIX. ) cicatrice, It.) 



1. The scar remaining after a wound. 



2. In conchology, the glossy impression 

 in the inside of the valves, to which the 

 muscles of the animal have been affixed. 



CI'DARIS. (cidaris, Lat.) A family of 

 echini tes, characterised by being hemi- 

 spherical, globular, or sub-oval ; with 

 porous ambulacra, diverging equally on 

 all sides, from the vent to the mouth ; 

 vent vertical ; mouth beneath, and central. 

 The name cidaris has been given to them 

 from their supposed resemblance to tur- 

 bans. From other characters, derived 

 from their spines, they have obtained the 

 names of sea-urchins, sea-hedgehogs, sea- 

 thistles, &c., and those in a petrified 

 state, have obtained various names, ac- 

 cording to the particular, fanciful, and 

 erroneous notions which have been enter- 

 tained respecting their origin. Thus, 

 they were called ombria, fromo/i/Spcc, Gr. 



signifying the heavy rain, in which it was 

 supposed they fell ; brontia, from fipovrr), 

 from an idea that they were thrown to 

 the earth by thunder ; ceraunii lapides, 

 from KtpavvoQ, under an impression that 

 they were formed in the air and generated 

 by lightning ; chelonites, from their re- 

 semblance to the shells of the tortoise ; 

 and ova anguina, from their being sup- 

 posed to be the eggs of serpents. Par- 

 kinson. 



The species are numerous. 

 CI'LIA. (from cilium, Lat.) 



1. The eye-lashes. 



2. Hair-like vibratile organs. The organs 

 of motion in the radiated animals. The 

 cilia resemble very minute hairs, and are 

 only visible with the microscope. In the 

 simpler forms of animals, the cilia are 

 the organs for motion, respiration, and 

 the obtaining of food. Dr. Grant ha& 

 calculated four hundred millions of them 

 on a single flustra foliacea. 



CI'LIATED. Fringed, or edged, with paral- 

 lel hair, bristles, or appendages ; occupied 

 with short stiff hairs. 



CINE'REOUS. (cinereus, Lat.) Of a dark 

 grey, with a prevalence of black ; of the 

 colour of wood-ashes. 



CINERI'TIOUS. (cinericius, Lat.) Ash- 

 coloured ; resembling ashes. 



CI'NNABAR. (from icivvaflapi, Gr. cinabre r 

 Fr. cinabro, It.) The mercure sulphure 

 of Haiiy. Native cinnabar is a red, heavy, 

 sulphureous ore of quicksilver, the prin- 

 cipal mines of which are at Idria ir 

 Carinthia, and at Almaden in Spain. 

 Cinnabar is called " ore of mercury," 

 since from it mercury is obtained. 



CI'NNAMON-STONE. A blood-red, or hya- 

 cinth-red, variety of the dodecahedral 

 garnet. It consists of silica, alumina, 

 lime, and oxide of iron. The finest spe- 

 cimens are brought from Ceylon, where 

 it is found in the sand of the rivers. It 

 is also called Essonite. 



CI'RCULAR. A round surface with its dia- 

 meter equal on all sides. 



CI'RRIPEDE. An annulose, articulated, 

 animal without jointed feet. Cirripedes are 

 not plentiful, and are found only in the 

 upper secondary, and in tertiary deposits. 



CI'RRHOPOD. (from cirrus, Lat. and 

 TTowg, Gr.) The cirrhopods, or cirrho- 

 poda, like the entomostraceous Crustacea, 

 are articulated animals, enclosed in shells 

 like those of mollusca, so that they pre- 

 sent both forms of the skeleton. The 

 cirrhopods are almost always inclosed in 

 multivalve shells, secreted from the outer 

 surface of a fleshy, thin, enveloping, man- 

 tle, and are attached to submarine bodies 

 either directly, by their base, or by 

 means of a fleshy tubular peduncle. The 

 barnacle is an example of the cirrhopoda. 



