"Now what, Nathan?"
"Oh, that bag is full of dead things, of what you might call the bones of these bits of creatures, the shells off one of those tiny things like mussels. They are things that have gone in and have got all melted up."
"Here is another," said the schoolmaster, putting a lighter green sac in place, also cut open. "What now?"
"That is the very sac the water-bear looked into to see something kicking. The kicking thing was another water-bear. Now it is dead. The one that went in just now is kicking, too."
The schoolmaster took that sac also, opened it, and released the struggling water-bear.
"What now, Nathan?"
"He is out, but he doesn't feel good. He doesn't swim round as he did before he went in. I think he is going to die, schoolmaster. Oh, here is another bear just going into a sac. Let him out quick, won't you?"
The schoolmaster opened the sac and the freed little animal swam off.
"He got out, right off, and nothing but him," said Nathan. "Schoolmaster, isn't it queer that when they look in and see the dead ones, and the bones and skins, or see other ones caught and kicking, and can't get out, that they don't learn better than to go in themselves? I should think they'd have sense to keep out!"
"People do not have sense to keep out when the circumstances are just about the same. Now, all of you children, listen. You know that Nathan has told you
