CHAPTER IV. 

EXPERIMENTS. 

When Jonas had finished nailing down the corner, he said, "Now there are several experiments, which we can perform with the bellows. I will be the professor, and you two shall be my class in philosophy, and I will direct you how to make the experiments. 

"First," said Jonas, "you, Rollo, may take hold of the nose of the bellows with your hand, in such a way as to put your thumb over the end of it, to stop it up, and then let Nathan try to blow." 

Rollo did so, and Nathan tried to blow. He found that he could open the bellows very easily; but when he attempted to press the sides together again, he could not. He crowded the handle belonging to the upper side down, as hard as he could, but it would not move. 

"What makes it do so?" said Nathan. 

"The air inside," said Jonas. "We have stopped up all the places, where it could get out. The valve stops itself. Rollo stops the nose with his thumb, and I have nailed the leather down close, about all the sides. And so the air can't get out, and that keeps you from bringing the sides together again." 

Nathan tried again with all his strength. The sides came together very slowly. 

"They're coming," said he. 

"Yes," said Jonas. "They come a little, just as fast as the air can leak out through the little leaks all around." 

"I thought you stopped all the leaks," said Nathan. 
who wants to be a teacher? what are they doing? what is the name of the meeting? what is the name of a student? what tool were they using? who else was a student? what tool was he struggling with? what makes it work? what is it made out of? what did nathan think he stopped?
jonas making the experiments unknown Rollo unknown Nathan unknown The air inside leather all the leaks