1821."] of Chlorine and Carbon, %c. 107 



decomposed, muriatic acid will be liberated, and charcoal left. 

 The sublimed portion is then to be dissolved m alcohol, and 

 poured into a weak solution of potash, by which the substance 

 is thrown down, and the muriatic acid neutralized and separated ; 

 then wash away the potash and muriate by repeated affusions 

 of water, until the substance remains pure ; collect it on a 

 filter, and dry it, first between folds of paper, and afterwards by 

 sulphuric acid in the exhausted receiver of the air-pump. 



It will now appear as a white pulverulent substance ; and if 

 perfectly pure will not, when a little of it is sublimed in a tube, 

 leave the slightest trace of carbon, or liberate any muriatic acid. 

 A small portion of it dissolved in ether, should give no precipi- 

 tate with nitrate of silver. If it be not quite pure, it must be 

 resublimed, washed, and dried until it is pure. 



This substance does not require the direct rays of the sun for 

 its formation. Several tubes were filled with a mixture of one 

 part of defiant gas with five or six parts of chlorine, and placed 

 over water in the light of a dull day ; in two or three hours 

 there was very considerable absorption, and crystals of the 

 substance were deposited on the inside of the tubes. I have 

 also often observed the formation of the crystals in retorts in 

 common day light. 



A retort being exhausted had 12 cubic inches of olefiant gas 

 introduced, and: 2.4-75 cubic inches of chlorine : as soon as the 

 condensation occasioned by the formation of the fluid had taken 

 place, 21-5 cubic inches more of chlorine were passed in, and 

 the retort set aside in a dark place for two days. At the end of 

 that time muriatic acid gas and the solid chloride had formed, 

 but the greater part of the fluid remained unchanged. Hence it 

 will form even in the dark by length of time. 



I tried to produce the chloride by exposure of the two gases 

 in tubes over water to strong lamp-light for two or three hours, 

 but could not succeed. ■ 



The perchloride of carbon, when pure, is immediately aiter 

 fusion, or sublimation, a transparent colourless substance. It 

 has scarcely any taste. Its odour is aromatic, and approaching 

 to that of camphor. Its specific gravity is as nearly as possible 2. 

 Its refractive power is high, being above that of flint glass 

 (1-0767). It is very friable, easily breaking down under pres- 

 sure ; and when scratched has much of the feel and appearance 

 of white sugar. It does not conduct electricity. 



The crystals obtained by sublimation and from solutions of 

 the substance in alcohol and ether, are dendritical, prismatic, 

 or in plates ; the varieties of form, which are very interesting, 

 are easily ascertained, and result from a primitive octohedron. 



It volatilizes slowly at common temperatures, and passes, in 

 the manner ofi camphor, towards the light. If warmed, it rises 

 more rapidly, and then forms fine crystals : when the tempera- 

 ture is further raised, it fuses at 320° Fahr. and boils at 360° 



