“But, Royal,” said Lucy, “what good does it do to put in the box? Why don’t you pour the water right into the hole.”
“Because,” said Royal, “it would all soak away into the ground. The sides of the box will keep the water from soaking away so much.”
“It will soak away through the cracks,” said Lucy.
“No,” said Royal, “I shall stop up the cracks.”
Accordingly, when Royal had finished placing his box in the ground, and had packed the earth in tight all around it, he went away with his wheelbarrow to a bank at some distance, down in the field, where there was some clay, and he brought a little of this in his wheelbarrow to the spot. He worked this clay over all the seams, and into the corners of the box, ramming it down hard.
“There,” said he, “now the water can’t get through. Clay is water-tight. Water can go through sand, but it can’t get through clay.”
“Is that what you mean by water-tight?” asked Lucy.
“Yes,” replied Royal. “After I have made my box water-tight, with clay, then I am going to put sand in.”
“What is that for?” said Lucy.
“You will see,” replied Royal.