CAT 



C E N 



escence resembling the light from the eye 

 of the cat ; whence its name. The pecu- 

 liar play of light arising from the struc- 

 ture of this stone, is better known than 

 susceptible of description. The finest 

 specimens are brought from Ceylon. 

 Cat's-eye is harder than quartz, and con- 

 sists of silex 95, alumine 1*75, lime 1'25, 

 oxide of iron 0'25. 



CATO'DON. A name given to the sperma- 

 ceti whale. Of the genus Catodon, Ray 

 mentions a large one stranded on the 

 coast of Holland. 



CATOCY'STI. The second great division, or 

 family, of Echini. The catocysti have 

 the opening for the vent in some part of 

 the base of the shell ; they are divided 

 into fibulse, cassides, scuta, and placenta?. 



CAU'DA. (Lat.) In conchology, the elon- 

 gated base of the ventre, lip, and colu- 

 mella. 



CAI/DAL. (from cauda, Lat.) Relating 

 'to the tail ; as the caudal fin of a fish. 



CAU'DATE. } (caudatus, Lat.) That hath 



CAU'DATED. $ a tail; tailed; having a 

 long termination like a tail. 



CAU'DEX. (Lat.) The stock or trunk, the 

 stem or body of a tree. 



CA'VERNOUS. (cavernosus, Lat. caverneux, 

 Fr. cavernoso, It.) Full of caverns or 

 hollows. 



CAWK. A name for sulphate of barytes. 



CELE'STINE. Sulphate of strontia, or sul- 

 phate of strontites. It has obtained the 

 name of celestine from being frequently 

 found possessing a blue colour, but as it 

 does not invariably possess that colour, 

 and is often found either colourless or 

 red, the name appears to be inappropriate. 

 It occurs both massive and crystallized. 

 It is composed of 58 parts of strontia, and 

 42 of sulphuric acid. It is found in Scot- 

 land, in Yorkshire, and in Somersetshire, 

 near Bristol ; also in the neighbourhood of 

 Paris, and in Sicily, from which last place 

 we obtain the finest specimens. 



CELLEPO'RA. Animals belonging to the 

 class Vermes, order Zoophytes. Generic 

 characters : Animal an hydra or polype ; 

 coral somewhat membranaceous, com- 

 posed of cells. Species : The principal 

 species are the Cellepora pumicosa, an- 

 nulata, spongites, &c. Crabb. 



CELL, (cella, Lat. cellule, Fr. cella, It.) 

 A cavity or hollow. 



CELLI'FEROUS. (from cella and/ero, Lat.) 

 Producing cells ; containing cells. 



CE'LLULAR. Having small cavities, hol- 

 lows, or cells. In botany, containing cells, 

 opposed to vascular. 



CE'LLULAR MEMBRANE. In anatomy, that 

 tissue of filmy meshes which connects the 

 minute component parts of most of the 

 structures of the body. 



CE'LLULAR INTEGUMENT. In botany, the 



succulent pulpy substance, situated im- 

 mediately under the cuticle ; the seat of 

 colour, mostly green, particularly in the 

 leaves or branches. Leaves consist al- 

 most entirely of this substance, covered 

 on each side by the cuticle ; the stems 

 and branches of both annual and peren- 

 nial plants are invested with it. This 

 tissue is membranous and transparent: in 

 its simplest state, it appears like a mass 

 of globules or vesicles, crowded together ; 

 these, by pressing against each other, as- 

 sume a six-sided, or hexagonal form. This 

 cellular tissue allows of the passage of 

 fluids, and is, consequently, porous, but 

 no pores or openings have been discovered 

 in it. Cellular integument is in itself 

 colourless, but its vesicles contain that 

 colouring matter which gives to the co- 

 rolla its brilliant colours, and to the her- 

 baceous parts of plants their green. 



CE'LLULE. (from cellula, Lat.) This may 

 be considered as the diminutive of cell, 

 and though, probably, frequently used 

 synonymously with cell, yet is strictly not 

 so : a small cell or hollow. 



CELLULI'FEROUS. Bearing, or producing, 

 cellules. 



CEME'NT. (ciment, Fr. cimento, It.) The 

 matter with which any two, or more, bo- 

 dies are made to cohere. 



CEMENTA'TION. (cementation, Fr.) 



1. The act of uniting by means of cement. 



2. A chemical process by which iron is 

 converted into steel ; glass into porcelain, 

 &c. This process is effected by sur- 

 rounding the body to be acted on with 

 some other substance, as iron with char- 

 coal, and subjecting it to the action of fire 

 in a closed vessel. 



CEMENTI'TIOUS. Having the property or 

 quality of uniting. 



CENTIFO'LIOUS. (from centum and fo- 

 lium, Lat.) Having a hundred leaves. 



CENTRI'FUGAL. (centrifugo, It. centri- 

 fuge, Fr. Terme de Physique. Un 

 corps qui se meut en rond, a une force 

 centrifuge.) That power which bodies 

 in rapid rotatory motion acquire of flying 

 off from the centre. The force with which 

 a revolving body tends to fly from the 

 centre of motion : a sling tends to fly 

 from the hand in consequence of the cen- 

 trifugal force. The centrifugal force 

 arising from the velocity of the moon in 

 her orbit, balances the attraction of the 

 earth. The dimensions of the earth being 

 known, as well as the time of its rota- 

 tion, it is easy thence to calculate the 

 exact amount of the centrifugal force, 

 which, at the equator, appears to be 5 |gth 

 part of the force or weight by which all 

 btrdies, whether solid or liquid, tend to -#- 

 fall towards the earth. 



CENTRI'PETAL. (centripete, Fr. Qui tende 



