"How deep do you have to dig to find water—to China?"
"Our wells are about thirty feet deep," said Frank. "In a dry time there's no water in them."
"How is it when you have a long wet spell?"
"They are more than half full then."
"Have both wells the same depth?"
"I think so."
"Where does the water in the wells come from?"
"It is the rain that has soaked into the ground," said Frank.
"How far down does it go?"
"It must go down till it finds some hard clay or rock that stops it," said Frank.