The rear wheels are the drivers, and must be fastened rigidly to the axle by glue. When the glue has hardened—this takes several hours—the machine may be sent across the room on the floor by winding the rear axle backward as much as the rubber bands will permit without breaking, and setting the machine on the floor.
The first time the boys tried it, the rubber band uncoiled so quickly that the auto shot across the room and nearly wrecked itself against the wall. This was too realistic, especially as it broke one of the forward wheels, and a new one had to be made.
When such an automobile is to be presented to little children who want to draw it around with a string, it is necessary to remove the rubber band; otherwise the rear wheels will drag.
When our boys had finished their machine, the question came up to whom it should be given for Christmas, and Harry blurted out, "I want it myself." This was the greatest of all their difficulties. When they had finished a piece of work they hated to part with it, but Ralph was older, and he knew that as Harry became interested in new things he would gradually lose interest in the old ones. So they played with this machine, made another with a roadster body, and auto races became the rage for awhile. After several afternoons of racing, they decided, just as their elders had done before them, that what their machines needed was improved motive power. The accomplishment of this would take them out of the realm of woodwork, so Ralph suggested that they stick to their motto of "one thing at a time." "And our business just now is woodwork."
[VIII]
THE MODEL AEROPLANE
The automobile experiment naturally suggested the aeroplane, and after much reading of magazines and animated discussions as to the relative advantages of biplanes, monoplanes, gliders, etc., the boys decided to try their skill on a biplane of their own design, a combination of the features and proportions of the Curtiss and Wright machines.
The automobile was child's play compared with the problems confronting the young aviators in designing and working out a flying machine, and, as in the former case, the question of motive power was the most difficult. We might add it has not yet been satisfactorily solved.
[Fig. 48] shows the general appearance of the boys' model, which was eighteen inches long from front to back, and the planes, made of light card-board, were 14 inches long and 31⁄2 inches wide. The frame, braces, rudder, and tilting plane were made of 1⁄8-inch basswood, put together with 1⁄2-inch brads clinched wherever the points came through.