of Chlorine and Carbon, &'c. 351 
voured, at first, to find how much chlorine was liberated from a 
certain weight of perchloride during its conversion into proto- 
chloride, and for this purpose distilled the perchloride through 
red-hot tubes into solution of nitrate of silver, receiving the gas 
into tubes filled with and immersed in the same solution; but I 
could never get accurate results in this way, from the difficulty 
of producing a complete decomposition, and also from the form- 
ation of chloric acid. Five grains of perchloride distilled in this 
manner gave 4:3 grains of chloride of silver, which are equiva- 
lent 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 pro- 
duced, and a little charcoal deposited. When the tube was cold, 
the barytes was dissolved in nitric acid, and the chlorine preci- 
pitated by nitrate of silver. 9:4 grains of dry chloride 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 peroxide 
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 chlo- 
ride of carbon to be one proportion of chlorine and one of car- 
bon, or 33°5 of the former, and 5:7 of the latter. The difference 
between these theoretical numbers, and the results of the experi- 
ments, 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 proto- 
chloride in excess over mercury by the electric spark. The ex- 
pansion 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 portion of the substance, 
giving rise to the second volume of the carbonic oxide, and to 
the calomel. 
A mixture of two volumes of hydrogen and one volume of 
oxygen 
