50 On two new Compounds [1820. 



tion ; but I could never get accurate results in this way, from 

 the difficulty of producing a complete decomposition, and also 

 from the formation of chloric acid. Five grains of perchloride 

 distilled in this manner gave 4*3 grains of chloride of silver, 

 which are equivalent to 1'06 grain of chlorine; but some of the 

 chloride evidently passed undecomposed, and crystallized in 

 the tube. 



2*7 grains of the pure protochloride were passed over red- 

 hot pure baryta in a glass tube : a very brilliant combustion 

 with flame took place, chloride of barium and carbonic acid 

 were produced, and a little charcoal deposited. When the tube 

 was cold, the barytes was dissolved in nitric acid, and the chlo- 

 rine precipitated by nitrate of silver. 9*4 grains of dry chlo- 

 ride of silver were obtained =2'32 grains of chlorine. 



Other experiments were made with lime, which gave results 

 very near to this, the quantity of chloride being rather less. 



Three grains of pure protochloride were passed over per- 

 oxide of copper heated red-hot in an iron tube, and the gas 

 received over mercury. 3*5 cubic inches of carbonic acid 

 gas came over, mixed with *1 of a cubic inch of common air. 

 These 3*5 cubic inches are nearly equal to '449 of a grain of 

 carbon. 



These experiments indicate the composition of the fluid 

 chloride of carbon to be one proportion of chlorine and one 

 of carbon, or 33*5 of the former, and 5*7 of the latter. The 

 difference between these theoretical numbers, and the results 

 of the experiments, is not too great to have arisen from errors 

 in working on such small quantities of the substance. 



A mixture of equal volumes of oxygen and hydrogen was 

 made, and two volumes of it detonated with the vapour of the 

 protochloride in excess over mercury by the electric spark. 

 The expansion was very nearly to four volumes ; of these, two 

 were muriatic acid, and the rest pure carbonic oxide : and 

 calomel had been formed, its presence being ascertained by 

 potash. Hence it appears, that one volume of hydrogen and 

 half a volume of oxygen had decomposed one proportion of the 

 protochloride, forming the two volumes of muriatic acid gas 

 and one volume of carbonic oxide ; and that at the intense 

 temperature produced within the tube by the inflammation, the 

 rest of the oxygen and the mercury had decomposed a further 



