2JO MURIATES AND CHLORIDES. 



evolved which ought to have been combined 

 with the oxygen, requisite to convert them into 

 protoxides, supposing that this oxygen had been 

 in the state of water. The reader will recollect 

 that the atomic weights of these bodies are as 

 follows : 



Iron . 3-5 



Zinc . 4-25 



Tin . 7-25 



Antimony 5-5 



Now, 3-5 grains of iron, 4'2<5 grains of zinc, 

 7'&5 grains of tin, and 5 '5 grains of antimony, 

 supposing these metals pure, give out, when dis- 

 solved in muriatic acid, exactly the same volume 

 of hydrogen gas ; namely, about 5*9 cubic inches 

 or -a of a grain. There seems no doubt from 

 this, that these metals during their solution com- 

 bine with oxygen, and that they derive this oxy- 

 gen from water, which is decomposed precisely 

 as when iron or zinc is dissolved in sulphuric 

 acid, the oxygen uniting to the metal, and the 

 hydrogen flying off. 



It would indeed be equally possible to account 

 for the evolution of the hydrogen gas by con- 

 ceiving the chlorine of the muriatic acid to com- 

 bine with the metal, while its other ingredient ? 

 the hydrogen, escapes under the form of gas ; for 

 the volume of hydrogen evolved on either sup- 

 positions, would be precisely the same ; but 



