When they reached home father drove to the ice house.
"Look in there," he said to Bobby, "and tell me what you see."
"I see a great pile of sawdust," said Bobby. "You won't put the ice in there will you, father? I do not want sawdust in my ice cream."
"We will see that no sawdust gets into the ice cream," said father, "and yet we could not make the ice cream without it."
Father carried the big cakes of ice into the ice house and piled them in rows on a deep layer of sawdust. Then he went for another load and another and another. All that week he kept drawing ice until the ice house was nearly full. Over the top of the ice and around the sides of it he packed sawdust until it looked like a mountain.
"Are you trying to keep the ice warm?" asked Bobby.
"No, Bobby, I am covering it with the sawdust to keep it cool," said father.
"That is very strange," said Bobby. "Mother puts blankets on me to keep me warm. You put a blanket on the ice to keep it cool. I think there must be a mistake somewhere."
After a few months spring came and the snow melted and the ice on the river melted.
One day mother said, "If you will get me some ice we will have ice cream to-day. I am going to churn too and will need some for the butter."