Dr THOMAS THOMSON on a New Combustible Gas. 19 

 We have, from a well-known hydrostatical property of gases, 



. (A + B)c Aa 

 07 - g 



In the present case, 



A = 71 ; a 1.03384 ; 

 B = 29 ; c T945. 



(100)1-945 71 x 1-03384 4.1 ~ K v 

 Consequently, a? =- ' ^9 " = 41 757; 



4-1757 considerably exceeds the specific gravity of chloro-carbo- 

 nic acid, or the phosgene gas of Dr DAVY, which is 3*4722. 



9. I found by repeated trials, that the new inflammable gas, 

 (the nitrous gas being removed by means of oxygen gas and pot- 

 ash), requires for complete combustion twice its volume of oxy- 

 gen gas. The mean of five experiments gave 12 volumes in- 

 flammable gas, and 24,38 volumes of oxygen gas consumed, when 

 an electric spark was passed through the mixture over mercury. 

 The only products after the combustion were calomel and carbo- 

 nic acid gas. 



When the detonation of the mixture of the inflammable 

 gas and oxygen was made over a little water, holding nitrate of 

 silver in solution, the liquid became milky, owing to the forma- 

 tion of chloride of silver. It is obvious from these facts, that two 

 of the constituents of the gas are chlorine and carbon. 



A mixture of 12 volumes of gas, and 24*38 volumes of oxy- 

 gen, left, after detonation over mercury, 15*43 volumes of car- 

 bonic acid gas. This is a mean of four experiments, which did 

 not agree very well with each other ; two of them giving only 

 13*89 volumes of carbonic acid, and the other two 15.98 volumes. 

 I made twelve additional experiments, with a view of getting re- 

 sults more to be depended on. But the mean of the whole 

 scarcely differed from 15.43, and the same discordancy appeared 

 in the new as in the old experiments. 



c2 



