356 Royal Society. 



gas, and he therefore gives it the name of the chloro-nitrous gas. 

 When collected over mercury, one portion of it forms with that metal 

 a white compound, which appears to be a mixture of calomel and 

 corrosive sublimate, whilst the remainder is found to give orange 

 vapours with common air, attended with a diminution of volume, 

 and to be almost wholly absorbed by a recent solution of green sul- 

 phate of iron. He also infers that the gas consists of equal volumes 

 of chlorine and nitrous gas, combined together without any conden- 

 sation, its atomic number being 102. He finds its specific gravity, 

 compared with that of atmospheric air, to be 1.759. 



In the mutual decomposition of chloride of sodium and nitric acid, 

 the products appear to be chloro-nitrous and chlorine gases, and 

 nitrate of soda. The author explains the changes which take place in 

 the following manner : the nitric acid, by its partial decomposition, 

 yields nitrous gas and oxygen : the former unites with part of the 

 chlorine expelled from the chloride of sodium, to form chloro-nitrous 

 gas, whilst the latter combines with the sodium to form soda, which, 

 with the remaining nitric acid, compose nitrate of soda. The re- 

 mainder of the chlorine mixes with the chloro-nitrous gas. 



The author states that the two component gases of the chloro- 

 nitrous gas unite at once when brought into contact, after having 

 been dried in the most careful manner possible ; a fact which is con- 

 trary to the opinion generally entertained among chemists. 



By passing chloro-nitrous gas through water an acid is obtained, 

 which appears to resemble very closely the common solvent of gold, 

 or aqua regia, otherwise called the nitro-muriatic acid. The author 

 here remarks, that if the constitution of the chloro-nitrous gas be 

 such as he has stated, that is, composed of 30 by weight of nitrous 

 gas and 72 of chlorine, one of its proportionals should decompose 

 two of water, consisting of 1 6 oxygen and 2 hydrogen ; thus form- 

 ing 46 nitrous acid, and 74 muriatic acid. But an acid so consti- 

 tuted should be incapable of acting on gold or platina ; now the acid 

 resulting from the absorption of chloro-nitrous gas by water has 

 this power. 



The author concludes from his experiments, that the power of 

 nitro-muriatic acid in dissolving gold is not owing to the liberation 

 of chlorine, and that muriatic acid may be separated from nitric acid, 

 even when the latter is only half the volume of the former. He re- 

 gards chlorine and chloro-nitrous gases as the gaseous products 

 arising from the mutual action of strong nitric and muriatic acids on 

 each other. The nitro-muriatic and chloro-nitrous acids strongly 

 resemble each other in their action on platina, though the solvent 

 power of the latter is decidedly greater than that of the former ; and 

 the addition of water considerably increases this power in both, pro- 

 bably by counteracting their disposition to assume the elastic state. 

 Both acids form, with different bases, salts which are mixtures of 

 nitrates and chlorides. The principal differences in these acids may 

 arise from their mode of preparation, and is probably due to the want 

 of uniformity in their composition. 



Feb 24. A Paper was read, entitled, " On the Chemical Action 



of 



