6 o Mr. Faraday on two new compounds 
I shall now give the reasons which induce me to consider.it 
a true chloride of carbon, and shall endeavour to assign its 
composition. My first object was to ascertain whether hy- 
drogen existed in it, or not. When phosphorus is heated in 
it, a small quantity of muriatic acid is generally formed ; but 
doubt arises as to the cause of its production, from the cir- 
cumstance that the phosphorus, as already mentioned, may 
be the source of the hydrogen. When potassium is heated 
in the vapour of the substance, there is generally a small ex- 
pansion of volume, and inflammable gas produced ; but it is 
very difficult to cleanse potassium both from naptha and an 
adhering crust of moist potash ; and either of these, though 
in extremely minute quantities, would give fallacious results. 
A more unexceptionable experiment made with iron, has 
been already described ; and the inferences from it are against 
the presence of hydrogen in the compound. 
Some of the substance in vapour was electrized over 
mercury, by having many hundred sparks passed through it. 
Calomel was formed, and carbon deposited. A very minute 
bubble of gas was produced, but it was much too small to 
interfere with the conclusions drawn respecting the binary 
nature of the compound ; and was probably caused by air 
that had adhered to the sides of the tube when the mercury 
was poured in. 
The most perfect demonstration that the body contains no 
hydrogen, and indeed of its nature altogether, is obtained 
from the circumstances which attend its formation. When 
the fluid compound of chlorine and olefiant gas is acted on 
by chlorine and solar light in close vessels, although the 
whole of the chlorine disappears, yet there is no change of 
