"What?"
"That debt."
"What debt?"
"Why, the interest on the mortgage."
"I don't know what you are talking of."
"Why," said Rufus a little impatiently, "don't you know that when papa bought the property he couldn't pay off the whole price right down, and so he was obliged to leave the rest owing, and give security."
"What security?"
"Why, a mortgage on the farm, as I told you."
"What do you mean by a mortgage?"
"Why, he gave a right over the farm — a right to sell the farm at a certain time, if the debt was not paid and the interest upon it."