'No; it comes out of the ground.'
'This is like the slate story,' said Dora.
Harry nodded.
9. 'But, Joe, I want to know how the chalk makes the ground good.'
'I don't know how, but it does. If it lies here for a year or more, the earth will turn brown, and we can grow wheat in it. Besides, chalk holds water, and so it will keep the ground moist up here.'
10. 'How?'
'Well, when it rains, the water will not run away through the earth, but will stay in the lumps of chalk. Are you going? Good-bye, then.'
