ATTRACTION. 1(57 



tablished by Gay Lussac, and Humboldt,* and the first fact of the 

 kind observed, was in the case of the elements of water, two vol- 

 umes of hydrogen combining with one volume of oxygen. 



The following tablesf exhibit a number of facts of this class. 



Volumes. Volumes. 



100 muriatic acid gas combine with 100 ammoniacal gas. 



100 carbonic acid gas, " " 100 do. do. 



100 do. do. " 200 do. do. 



100 nitrogen gas, " " 50 oxygen gas, 



100 do. " " 100 do. 



100 do. " " 150 do. 



100 do. " " 200 do. 



100 do. 250 do. 



100 Chlorine gas, " " 100 hydrogen gas. 



100 nitrogen gas, " " 300 do. 



100 oxygen gas, " " 200 do. 



This table needs no comment ; supposing it to be accurate, of 

 which there can be no reasonable doubt, it fully supports the propo- 

 sition stated above. 



(yy.) Bodies in the state of vapor obey the same law. 

 11 100 vols. hydrogen + 100 vols. vapor of sulphur = sulph'd hydrogen, 

 100 " oxygen -j- 100 " " = sulphurous acid. 



100 " " -f-100 iodine = hydriodic acid."J 



This view is carried so far as even to embrace solids, which, per- 

 haps, have never been in the aeriform condition, except in a state of 

 combination ; it is supposed that in that state, they would obey the same 

 rule. In the compound gases just mentioned, it is obvious that the 

 specific gravity and proportion of the oxygen in sulphurous acid, and 

 of the hydrogen in sulphuretted hydrogen being known, the balance 

 of the weight of the gas under a given volume, must represent the 

 sulphur in the state of vapor ; and the same remark will apply to the 

 hydriodic acid ; we may include the carburetted hydrogen gases in 

 the same view, for the specific gravity of the hydrogen which they 

 contain, and its proportion being known, it is obvious that the remain- 

 der of the weight in a given volume must be carbon in a state of 

 vapor. 



(zz.) When gases suffer condensation, in consequence of com- 

 bining, it is always in a simple ratio to the volume of one of them. 

 Ammonia is composed of 3 vols. of hydrogen -f 1 vol. of nitrogen, 

 contracted into 2 vols. and in the formation of nitrous oxide gas there 



Memoires d'Arcueil. t Murray, 6th Ed. Vol. 1, p. 67. 



