DEFINITION OF TERMS. 



71 



Calyx — Among botanists, a general 

 term expressing the cup of a flovver,or that 

 part of a plant which surround and sup- 



J ports the other parts of the flower. 

 Camphoric %^cid^ls the result of the 

 change produced on camphor by distilling 

 nitric acid several times from it. It crys- 

 tallizes in parallelopipeds, is efflorescent, 

 soluble in water and volatile in a strong 

 heat. 



Caoutchouc — (Gum Elastic or Indian 

 rubber) is the produce of several trees in 

 South America and the East Indies. It is 

 partly soluble in volatile oils and entirely 

 so in Naphtha, melted spermaceti and in 

 nitric ether. 



! Capillary Tubes. — In Physics little 

 pipes, whose canals are extremely narrow. 

 The principle which causes water or other 

 fluid substance to ascend in those tubes as 

 in a sponge, or the interstices of linen 

 cloth and many other substances is called 

 capillary attraction. 



Capsule — Among botanists, a species 

 of pericarpium or seed vessels, Caput 

 Mortum in Chemistry, that thick dry 

 matter which remains after distillation of 

 any thing but of minerals especiall}'. 



Carbon — Or the radical of carbonic 

 acid, has not, unless the diamond is admit- 

 ted as such, been j-et obtained in a separate 

 state. It; is infusible and indissoluble by 

 caloric and is hence esteemed the most re- 

 fractory substance in nature. Its specific 

 gravity is about 3.5. 



When the diamond is burnt in oxygen 

 by the solar rays carbonic acid is produc- 

 ed without residue. One part of diamond 

 absorbing four of oxygen and producing 

 fire or carbonic acid. 



In proportion as substances contain pure 

 combustible matter will, in fact, be the 

 difficulty of their combustion, their first 

 degrees of oxygenation proceeding slowly. 

 Thus plumbago, and anthracolite, Kilken- 

 ny coal, the brilliant charcoal of certain 

 vegetables will not burn except at a very 

 high temperature. 



The diamond is therefore considered as 

 pure carbon, plumbago, carbon oxygeniz- 

 ed in the first degree. 



Charcoal — An oxyde of the second de- 

 gree, obtained from various substances in 

 the animal, vegetable, and mineral king- 

 doms, generally by volatilizing their other 

 constituent parts. 



When obtained in a slate of pur i'y it 

 resists the strongest heat in closed vessels 



It decomposes sulphuric acid from its 

 affinity with oxygen exceeding that oi 

 sulphur. It decomposes nitric acid with 

 great rapidity : and if the charcoal is first 

 powdered, and the acid strong and allow- 

 ed to run down the side of the vessel, to 

 mix with the charcoal, it burns with ra- 

 pidity, vvitli a beautiful flame, throwing up 

 the powder so as to resemble a beautiful 

 lire-work. 



With nitrate of pot-ash it detonates in 

 a hot crucible, leaving a fixed alkali be- 

 hind. It is dissolved by the alkalies, and 

 by the suljihurets of alkali, both in the 

 dry and moist way. It does not unite with 

 metals but restores their oxydes to a me- 

 tallic state. 



Charcoal possesses the power of absorb- 

 ing several gasses which thus condensed 

 retain their properties and even exert 

 them in some instances more powerfully. 

 It decomposes water at the common tem- 

 perature, carbonic acid and carbonated hy- 

 drogen being separated. If burnt in con- 

 tact with coni'iion air its acidifiable l)ase at- 

 tracts oxj'gen, and this peculiar acid is 

 formed, which, with a certain proportion 

 of caloric, assumes a gasseous form. If 

 burnt in oxygen gas, its peculiar acid is 

 plentifully formed, the charcoal burning 

 with considerable increased rapidity and 

 if the lighter charcoal made from bark is 

 used a very brilliant effect is produced 

 from the numerous vivid coruscating 

 sparks. 



Carbonates — Are neutral salts compos- 

 ed of the carbonic acid and certain bases, 

 thus carbonate of ammonia, or mild vola- 

 tile alkali consists of carbonic acid and 

 pure or caustic ammonia, owing to the 

 weakness of this acid, the characters of 

 their bases are generally, most predomi- 

 nant. 



The carbonates are not acted on by light 

 or oxygen or nitrogen; nor do they deli- 

 quesce with the moisture of the atmos- 

 phere. 



All the other acids have a greater attrac- 

 tion for the earthy and alkaline bases than 

 carbonic. 



Car?nine — A powder of a very beauti- 

 ful red color, bordering on purple, and 

 used by ])ainters in minature though but 

 rarely because of its great price. 



