To Mount the Wheel upon its standard, whittle an axle 8½ inches long to fit the hubs, then hold the wheel between the two uprights, with the hubs on a line with the spool bearings and run the axle through the holes (Fig. 137).
Build Steps at each end of the platform out of heavy writing-paper or light cardboard. Fold the paper or cardboard back and forth, making pleats about ¼ inch wide for the steps, and after gluing it in place cut out the balustrades and glue them to the edges of the steps. Make the top step low enough so there will be about ¼-inch clearance between it and the bottom of the cars (Fig. 137).
After you have made a final inspection to see that everything has been put together properly, your toy will be ready for operation, and I am sure that when you set the clockwork machinery in motion, and the little wheel begins to revolve slowly with each little car balancing upon its axle, you will agree that you have constructed a very interesting toy.
The "Flying Airships" is a riding device consisting of a number of cars suspended by steel cables from large arms pivoted to the top of a tower. When the machinery is started, the arms begin to revolve slowly, and the motion produced causes the cars to swing out away from the center. As the speed of the arms increases, the cars swing out farther and farther, until when the highest speed has been reached the cables by which the cars are suspended have taken an oblique position and raised the cars some distance above the ground; then the speed of
