PROPERTIES OF HYDROGEN. 87 



at present, but I will gently turn this jar of 

 hydrogen up under this other jar (fig. 28) and 

 then we will examine the two. "We shall see, 

 on applying a light, that the hydrogen has left 



Fig. 28. 



the jar in which it was at first, and has poured 

 upwards into the other, and there we shall 

 find it. 



You now understand that we can have par- 

 ticles of very different kinds, and that they can 

 have different bulks and weights ; and there are 

 two or three very interesting experiments which 

 serve to illustrate this. For instance, if I blow 

 soap bubbles with the breath from my mouth 

 you will see them fall, because I fill them with 

 common air, and the water which forms the 

 bubble carries it down. But now if I inhale 

 hydrogen gas into my lungs (it does no harm 



G 4 



