To him and Jimmy study was recreation. Mathematical problems were interesting to them, just as the solution of puzzles interests the boy in civilization. Just as the boy in civilization will work for hours upon the solution of a mechanical puzzle, they worked upon problems in arithmetic and geometry, and with the same gusto. They studied grammatical construction much as they studied the tracks and the habits of wild animals. They read the books in Skipper Ed's library with the feelings and sensations of explorers. In the first reading they were going through an unknown forest, and with each successive reading they were retracing their steps and exploring the trail in minute detail and becoming thoroughly acquainted with the surrounding country.