Full-Size.

Model No. 9. - Round Ruler.

Have the pupil cut from a 7-8" board a piece 1" x 13" and from this prepare an oblong 13-16" x 13-16" x 12 1-64". Quadrisect all edges of both ends and join opposite points except middle points. Plane corners to lines making an octagonal prism. Model corners with the plane making a cylinder. Round the ends with knife according to drawing and finish with file and sand-paper.