"I see little live things; some have little shells on them like mussels, only they look about as big as tiny pin-heads. Some have little whirling wheels on their heads. A good many are like very, very wee caterpillars."
"Those last are the water-bears," said the schoolmaster. "Now look at the bladder-plant."
"The bladders," said Nathan, "are little bags. Their mouths are open. They are set round with hairs. Some of the bags look full of something, and dark. Some of them seem to have some live thing kicking in them. Some are empty, and as you look in at the door it is like a little clear green room. Oh! I see a water-bear swimming up to one! He looks in. He seems to think it is pretty. I guess he wants to know where there is something kicking. He looks in there. Now he goes to an empty one. Now he swims by. No, he changes his mind. He thinks he will go in. He pokes in his head. The little hairs at the door bend inward: they let him go in easy. He is in! Oh! now he is trying to come out!"
Great excitement in the listening school—eyes wide open, heads bent forward.
"Can he get out?" cried someone.
"No! no! he can't," exclaimed Nathan, all eager. "The hairs bend in, and let him in, but he cannot get by them to go out! They won't bend out. Oh, he can't get out."
The schoolmaster now took one of the dark, full sacs, cut it open with a very fine, sharp instrument, and put it under the glass.
