Motoring on Roller-Skates
��II' \vc had wliL'cls on our fec-t, some- thing like the wings on Mercury's heels, would we "get there" much more quickly? Walking is admittedly an energ\-consuming method of loco- motion. A man's legs weigh fort\' or fifty pounds apiece, and the sheer labor of shifting them one ahead of the other means a considerable expcn-
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��Fig. 1. The driving agency is a small gasoline engine in the rear of each skate
diture of energy. Placing the same weight on the respective pedals of a bicycle will convey a man much farther. Wheeled locomotion has time and again demonstrated itself to be the most efficient method of getting over the ground.
This leads up to the subject of roller- skates. Why is it they are not more in use? A man on skates can propel him- self half a block with a stroke or two. Is there any reason wh>- their use should be confined to children? Is it the dignii>- of the thing? .Assuredly Americans never stop for dignity if a new con- tri\ance will get them where the\' want to go laster than has before been possible.
Scores of different kinds of roller- skates have been in\ented. All the in- ventors appear to be striving toward an unattainable ideal, and each approaches the problem from a different angle. The ordinary four-wheeled skate such as children use is too tame for most inventors. The>- would make the vehicle
��self-propeling, appareniU- believing that therein lies the secret of the ultimate roller-skate.
The easiest way to make a skate propel itself is to put something on it to do the propcling. In some forms the dri\iiig agency is a small gasoline engine; mounted at the rear. (Figs, i and 7.) The machines have shaft or chain-drive and are complete as to detail, some of them resembling miniature Ford auto- mol)iles. They even have a gasoline tank under the instep and heel-part of the skate, the heel-brace being shaped somewhat like a miniature automobile -seat. The great difficulty with the gasoline engines which must be employed is that the cylinders are so small. It is hard to get an explosive mixture into
���Fig. 2. A sort of pantograph-motion causes the rear wheel of this skate to revolve
them and to discharge the burnt gases. Consequently the engines are inoperative three-fourths of the time. Other self- [iropeled skates have been made along similar lines, but driven by an electric motor. These have, on the whole, been more successful.
The second general t>pe is also self- propeling, but utilizes the weight of the rider in some way to supply the drixing agency. The methods of doing this are legion. Most of them depend on the fact that a man raises his foot in taking a step forward. In swinging his weight onto this foot he exerts downward pres- sure on his heel. The skate shown in