"How do you know when it is noon?"
"Why, the sun is highest at noon." said Donald. "and the shadows point straight toward the north."
"Early in the morning they point to the west," said Frank, "and in the evening they point to the east."
"The people who lived in the world many hundred years ago observed the same thing," said Uncle Robert. "There was nothing so strange to them as the rising and setting of the sun. They loved the light that came with it. They feared the darkness that followed its going away. They told many interesting stories to explain this continued appearance and disappearance. Some thought the sun was a king riding through the sky in a golden chariot. Others looked upon it as a god and worshiped it.
"They soon learned that when it went away it was sure to come again, and as they saw how regularly it moved, they felt there must be some power back of it to guide it. Through this they were led to a belief in a Being that controlled all things.
"They watched the shadows, too, and saw them change just as you see them every day. They learned that the shadow is shortest when the day is half gone, and they called that time midday. So, by studying the length and direction of the shadows, they soon became able to judge the time of day.
"Then some one thought to set up a rod and mark the places where the shadow fell at sunrise, at sunset, and at midday. The space in between was divided for the hours. This was called a sun dial and was the first instrument ever made for telling time."
"When was the first one made?" asked Frank.
"That is not known," replied Uncle Robert, "but we read in the Bible of the sun dial of King Ahaz, who lived about eight hundred years before the time of Christ. That is the first record we have of one."
"How was it made?" asked Donald.