As each tool is taken up, the pupil should turn to part III and study carefully what is said about that particular tool; and each day, until the lessons are mastered, review what is said in regard to the use of the tools in the lessons and also the description of the tools in part III. Each new lesson depends very largely upon those' preceding. Therefore, only by a constant review will the pupil get the greatest possible benefit from his study. Although the directions are quite explicit, an abun dance of Opportunity is left for individuality in work.