"Come," she called, "it is going up already. See!"

"How fast it moves!" said Donald. "Hold it close to the stove, Susie.
Maybe it will go to the very top."

"Let us put it in cold water," said Frank. "It won't hurt the
thermometer, will it?"

"Not at all," was the reply. "Try it."

So they held it in the bucket of cold spring water.

"How fast it goes down now!" said Susie. "I wonder if it will go lower
than it did out on the porch. It's down to forty-eight."

"Why does Jane set the kettle of cold water on the stove?" asked Uncle
Robert, pointing to it.

"To boil the water," answered Susie.

"What makes the water boil?"

"Why, the fire, of course."

"How long will the stove stay hot?"

"As long as there is fire in it."

"Longer than that," said Donald. "It doesn't grow cold the minute the