"You are mistaken," said Uncle Robert. "The sun is farther from us in summer than it is in winter."
"But it's almost over our heads in summer," said Frank. "How can it be farther away?"
"The story of the warmth that the sun gives us is not told by distance," said Uncle Robert, "but by the length of the shadows at noon."
"How is that?" asked Donald.
"When is your shadow the longest?" asked Uncle Robert.
"In the evening," said Donald.
"In the morning," said Susie.
"When is your shadow the shortest?"
"At noon!" they all shouted.
"When is it coolest?"