"And now air at rest," replied Rollo.
"Pretty nearly," said his father.
"Yes, sir, entirely," said Rollo; "there is no wind at all, this morning: hold up your hand, and you can feel."
So Rollo stopped a moment upon the grass, and held up his hand to see whether there was any wind.
"I know there is not any wind that you can perceive in that way," said his father.
"How can we perceive it, then?" said Rollo.
"I'll tell you," replied his father, "when we get to the top of the hill."
They reached the top of the hill soon after this, and sat down upon a smooth stone. There was a very wide prospect spread out before them,—fields, forests, hamlets, streams,—and here and there, scattered over the landscape, a little patch of snow. The sun was just up, and the whole scene was very bright and beautiful.
"Now, father," said Rollo, "tell me how you know that there is any wind at all."
"I did not say that there was any wind. I said motion of the air."