Fig. 487
An ambitious and clever boy who has once grasped the principles on which flying-machines are made can think out many models for himself and copy some of the more elaborate ones. The biplane makes a very effective toy, but is omitted here because it is somewhat difficult to construct.
[CHAPTER XXIV]
MORE OLD-FASHIONED TOYS
Jacob's Ladder. This is a very old and ingenious puzzle and an amusing toy. It is very simply made. A number of blocks of wood must be made, 4" × 2½" × 3/8". Any number may be used, but not less than seven; twelve is a very good number.
Fig. 488
Fig. 489