I fell down and was almost buried in the snow.

"Then it was winter, wasn't it?" asked Uncle Robert.

"It must have been," said Frank.

[Illustration: Shadow stick.]

"And since you told us that the shadows at noon tell why it is warmer in
summer than in winter I've been watching them. They get shorter all the
time." "How would you like to measure the shadows every day," said Uncle
Robert, "and see if you can find out when they are shortest and when
they are longest?"

"How can we?" asked Susie. "Shadows are so queer."

"Yes," said Uncle Robert, "shadows are queer, but, if we take one that
doesn't jump as yours does, don't you think we can measure it?"

"Of course we can," said Frank. "We can use the house. That always
stands still."

"The house might do," said Uncle Robert; "but wouldn't it be better to
have a shadow stick?"

"Where can we get one?" asked Donald.

"What is it made of?" asked Frank.

"It is like this," said Uncle Robert, taking paper and pencil from his