rom the surface of the earth the air grows colder and colder, until at
last, when you get up to a certain height, it is cold enough to freeze."

"Is it so every where?" asked Rollo.

"Yes," said Mr. George. "If you were to put some water into a vial and
tie it to the tail of a kite, and send it up into the air _high enough_,
the water would freeze, and when it came down you would find the water
turned into ice."

"Should I?" asked Rollo. "Would it if I were to send the kite up in
America?"

"Yes," said Mr. George, "any where, all over the earth."

"I mean to try it," said Rollo.

"You can't try it very well," replied Mr. George; "for you could not
easily send a kite up high enough. It would take a very long time."

"How long?" asked Rollo.

"Why, that depends upon what part of the earth it is that you make the
experiment in," replied Mr. George. "At the equator, where the sun is
very hot, you would have to go up very high. In temperate regions, as in
Switzerland or in most parts of America, you would not have to go up so
high; and farther north, near the pole, it is only necessary to go up a
very little way."

"And how high must we go up in Switzerland?" asked Rollo.

"About eight or nine thousand feet, I believe," said Mr. George. "Some
of the Alpine summits are sixteen thousand feet high; and so the ice and
snow lie upon the upper portions of them all the time."

The young gentlemen remained some time longer in the pavilion, gazing
upon the stupendous scenery around them, and looking down the lake which
lay before them in the bottom of a deep and narrow valley and extended
in among the mountains much farther than they could see.

"We are going along that lake," said Rollo "are we not?"

"Yes," said Mr. George; "it is the Lake of Thun."

"We are going in one of the steamboats that are lying at the pier, are
we not?" said Rollo.

"Yes," said Mr. George; "unless you would prefer going along the shore."

"Is there a road along the shore?" asked Rollo.

"Yes," said Mr. George; "there are two, I believe, one on each side of
the lake. These roads run along at the foot of the mountains, far
enough, however, above the level of the lake to enable us to enjoy
excellent views of it. But we cannot see the mountains from it as well
as we can from the lake itself."

"Then," said Rollo, "if we go by the road we can see the lake best; and
if we go by the steamboat we can see the mountains best."

"Yes," said Mr.