“Why, Abe, it’s nothin’ but a terrapin,” interjected a boy.

“Don’t terrapins have feelings?” responded our hero.

“I don’t know whether they do or not,” replied the first-named boy, at the same time adding another coal of fire to the animal’s back.

“You shan’t do it, Nat, unless you are stronger than I am,” exclaimed Abraham, knocking the last coal from the animal’s back, and pushing the boy with the stick aside.

“You’re a chicken-hearted feller, Abe, as ever lived,” continued Nat. “I should think the terrapin was your brother.”

“Whether he is or not, you won’t burn him any more while I’m ’round.”

“That’s it,” said Dave Turnham, who stood looking on. “I go in for Abe. He wouldn’t hurt a fly.”

“He would if he trod on it,” retorted Nat, aiming to be funny.

Mr. Crawford had witnessed a part of this scene, and he came out at this stage of the affair, and rebuked the cruelty of the boys who were torturing the terrapin, while he commended Abraham for his tenderness.

“We are coming to the Rule of Three now,” said Mr. Crawford to Abraham, “and that will be all you can learn of me.”

“Is it hard?” asked the boy.

“It won’t be for you. I think you can get through it by the time your father wants you this spring.”

“Why is it called the Rule of Three?”

“I hardly know. Some call it Simple Proportion, and that is the true name for it. You will see a reason for it, too, when you come to master it.”

“What if I don’t master it?”

“I’ll risk you on that. It won’t be of so much use to you as what you have been over already. Some people don’t study it.”

“My father never studied arithmetic,” said Abraham.

“Nor mine. Not half the folks about here have studied it.”

“Father never had a chance to study it when he was a boy.”

“That’s the case with a good many.”

“Well, I can cipher now in addition, subtraction, multiplication, and division.”

“Yes, you understand these rules well, and you will always find use for them.”

Encouraged by his instructor, Abraham grappled with the so-called “Rule of Three.” It was somewhat more difficult for him to comprehend this rule than it was the previous ones; yet he was not discouraged. His discriminating mind and patient labour did the work for him, and he enjoyed the happiness of understanding Proportion by the time his school-days were over. We do not mean that he comprehended it fully, so as to be complete master of it, but he understood it, as we are wont to say that pupils understand the