The Mighty Deep 



which should mount skywards, not from being 

 full of hydrogen gas, but from being emptied 

 of air. Being then lighter than the atmosphere, 

 it would, he said, of course rise. 



So far as the reasoning went, it was faultless. 

 It only did not go far enough. 



The balloon being made, he named a day for 

 its ascent, and asked many friends to witness his 

 triumph. At the last moment, all air was with- 

 drawn ; and everybody waited in expectation, 

 hoping to see the novel balloon skim lightly 

 above their heads. 



But the inventor, while using strong materials, 

 had failed to make full allowance for the tre- 

 mendous pressure of the air, when counteractive 

 pressure from within should have been done 

 away with. As the air was drawn out, the sides 

 of the balloon collapsed, being crushed together 

 as an empty egg-shell may be smashed in a 

 boy's hand. Instead of soaring gaily upward, the 

 would-be aeronaut stood on earth, scanning with 

 disappointed eyes a flattened and useless shell. 



A diver going down into the sea has a much 

 increased weight upon his body ; but he does 

 not suffer from it to a serious extent, provided 

 that he is not raised or lowered too fast. Much 

 depends upon this. Both men and beasts can 



44 



