HYDROGEN AND OXYGEN. 57 



introduced into the tube E F ; the tube was then 

 brought to a red heat as before ; and, in the same 

 manner, the whole of the water in the retort A was 

 made to evaporate. 



In this experiment there was disengaged only 

 one kind of gas, which was inflammable ; there was 

 obtained of it about 406 cubic inches, weighing 15 

 grains. 



The 274 grains of iron put into the tube E F 

 were found to weigh 85 grains above what they did 

 when introduced ; and the water first employed 

 was diminished 100 grains. 



The volume of these iron shavings was found to 

 be greatly enlarged. The iron was scarcely any 

 longer susceptible of attraction by the magnet ; it 

 dissolved without effervescence in acids ; in a word, 

 it was in the state of a black oxyd, like that which 

 has been burned in oxygen gas. 



In this experiment there was a real oxydation 

 of the iron by the water, entirely similar to that 

 effected in the air by the aid of heat. 100 grains 

 of water were decomposed ; and of these 100 

 grains, 85 united to the iron, to reduce it to the 

 state of black oxyd ; these 85 grains, therefore, 

 consisted of oxygen ; the remaining 15 grains, 

 combined with caloric, formed inflammable 'gas. 

 It thence follows, that water is composed of oxygen 

 and the base inflammable gas, in the proportion of 

 85 to 15, or of 17 to 3. 



If it be true, as we have endeavoured to prove, 

 that water is composed of hydrogen combined with 

 oxygen, it thence results, that, by re-uniting these 

 principles, water ought to be produced. This, in- 

 deed, is what takes place when, into a vessel filled 

 with oxygen, a stream of hydrogen is introduced 

 and set fire to. 



