CAM 



r.VM 



< f>hol, it appears in the form of acicular 

 prisms. 



Camphor, though a concrete substance, 

 is even more volatile than the essential 

 oils. It evaporates quickly at the com- 

 mon temperature of the atmosphere, 

 losing in weight, and :m- angular frag- 

 ment becoming spherical ; :uul at a tern- 

 perature between 100 and 150, it sub-' 

 limes in close vessels unchanged. It is 

 highly inflammable, kindles very readily, 

 and burns with the emission of much 

 light, and with a dense black smoke, 

 which condenses into a smooth light char- 

 coal. Carbonic acid gas is produced, and 

 a portion of the peculiar acid which has 

 been named camphoric acid. 



Camphor is very sparingly soluble in 

 water. When triturated with it, it mere- 

 ly communicates its smell and taste to the 

 water, which remains odorous, and some- 

 what pungent, even when filtrated ; but 

 no appreciable quantity is dissolved. A 

 phenomenon which has excited some at- 

 tention is presented, when pieces of cam- 

 phor are placed on the surface of pure 

 water. They soon begin to move with 

 rapidity, and while moving dissolve, the . 

 solution taking place at the line where 

 the water and the air are in contact; as 

 is proved by immersing a cylinder of 

 camphor in water part of its length : it 

 becomes excavated, and at length is cut 

 through, exactly on a level with the sur- 

 face of the water. 



Camphor is abundantly soluble in alco- 

 hol : the solution is immediately decom- 

 posed, and the camphor precipitated in 

 the form of a white powder, by the affu- 

 sion of water; but if the water be very 

 slowly added, and merely in such a quan- 

 tity as to weaken the affinity of the alco- 

 hol to the camphor, the latter, in sepa- 

 rating, presents a deutritic crystallization. 

 It is also soluble in expressed and essen- 

 tial oils. The alkalies do not dissolve 

 camphor, or produce in it any sensible 

 change. Of the earths, magnesia appears 

 to exert some action on it, as, when they 

 are triturated together, the camphor is 

 reduced to a smooth impalpable powder, 

 which is easily diffused in water. The 

 action of the stronger acids on camphor 

 is peculiar, and presents some singular 

 results. 



By distilling nitric acid from camphor, 

 it is more completely changed, and by 

 this process is converted into an acid, 

 which has received the name of campho- 

 ric acid. The process consists in distill- 

 ing from four ounces of camphor in a re- 

 tort, lib. of nitric acid, so far diluted as 

 to be of the specific gravity of 1.33, the 



heat being gradually applied by the me- 

 dium of a sand-bath : nitric oxide and 

 carbonic a< re disengaged ; part 



ot the campho'- rises in vapour, while 

 the other part receives oxygen from the 

 acid. 



Camphoric acid, thu produced, is dif- 

 ferent from all the known acids. It has a 

 slightly lic'ul hi. ter taste, aiu 1 reddens in- 

 fusion of litmus. Its crystals effloresce 

 on exposure to the air ; they are sparing- 

 ly soluble in cold water, an ounce of wa- 

 ter at 50 of Fahrenheit not dissolving 

 more than 6 gr.iins; at 212, about 48 

 grains are dissolved. When the acid is 

 placed on ignited fuel, it emits a dense 

 aromatic vapour, and is entirely dissipat- 

 ed. Hy applying heat to it in close ves- 

 sels, it first melts and sublimes, but by a 

 higher heat its properties arc changed ; 

 it no longer reddens litmus, acquires an 

 aromatic smell, its taste is less penetrat- 

 ing, and it is no longer soluble in water, 

 or in sulphuric or muriatic acid. Nitri 

 acid heated on it turns it yellow, and dis- 

 solves it. 



Camphoric acid is soluble in the mine- 

 ral acids : it is likewise soluble in alcohol, 

 and in the volatile and fixed oils. It pro- 

 duces no change in sulphur. The salts, 

 formed by this acid, with the alkaline, 

 earthy, and metallic bases, are named 

 Camphorates. Their properties have 

 been examined by I .a Grange. Their 

 taste is somewhat bitter : they are de- 

 composed by heat, the acid being sublim- 

 ed : and they all exhibit a blue flame 

 when heated before the blow-pipe. The 

 alkaline and earthy camphorates are form- 

 ed by adding the camphoric acid to the 

 alkali or earth, either pure, or in the state 

 of carbonate ; the carbonic acid, in the 

 latter case, being disengaged. 



CAMPHOR AXES, ? See the preceding 



CAMPHOTUC Acid, 5 article. 



CAMPHOR twc, the tree from which the 

 camphor of the shops is prepared, being 

 a species of J.aurel. See LAURUS. 



CAMPHOKASMA, in botany, from 

 camphora, a genus of the Tetrandria Mo- 

 nogynia class and order. Natural orcle. 

 of Holorace.T. Atriplices, Jussieu. Es- 

 sential character: calyx pitcher-form. 

 two of the teeth opposite, and the alter- 

 nate ones very small ; corolla none ; cap- 

 sule one-seeded. There are five species, 

 of which C. monspeliaca, hairy campho- 

 rasma, is an annual plant, with trailing 

 branches, extending a foot or more in 

 length; leaves linear: the flowers are 

 produced from the joints, and are so 

 small as to be scarcely perceptible. 

 Native of France and Spain. The whole 



