Page:Popular Science Monthly Volume 91.djvu/277

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Popular Science Monthly

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��One Horsepower Will Run All the Watches in the World

AN astute French mathematician l\ has found that in certain watches the motions exceed two hundred million a year in little equal jumps. In the same time the outside of the average balance travels seven thousand five hundred miles. Yet despite this astonishing distance traveled by the ordinary watch the amount of power con- sumed is trifling. One horsepower is sufficient to run two hundred and seventy million watches. This is probably all the watches that are in existence. But if there should be more there would be enough power left in the one horsepower to run an additional thousand watches

���A self-contained motor-truck equipped with standard electric street car trolley pole and a storage battery

��The Latest Conceit in Timepieces — A Buttonhole Watch

IN spite of the fact that there is no article of jewelry more useful than the watch, it seems hard to stow it away in a suit of clothes. It has been tucked away in vest pockets and belts, attached either to an ornate chain or an inconspicuous ribbon, and has adorned the wrists of all classes.

But the very latest and most con- spicuous location yet chosen for it is in the buttonhole of a coat lapel. The buttonhole watch is nec- essarily tiny, and fits into gun metal case which i sembles a large-sized collar button in shape. When worn merely for the con- venience of the owner the watch is usually turned upside down so that the time may be seen at a downward glance, without even lifting the lapel of the coat.

It is said that the diminutive size of the watch does not interfere with the accuracy of the works. The principal ob- jection to wearing one of them just now is that the buttonhole is needed for flag emblems and liberty bond buttons.

��Making a Trolley-Car of the Motor-Truck

WHY can't motor-trucks and other commercial vehicles obtain their power from overhead trolley wires? So they can, if reports from Bradford, England, are true.

In Bradford a motor-truck with a trolley pole attached to its cab takes power from overhead street car wires. The truck runs along on the street-car tracks, contact with the rails being made by means of a cast- iron block to the steering gear. This block also steers the vehicle.

When the truck reaches the end of the street-car tracks, the rail con- tactor is lifted, the trolley pole pulled down, and the stor- age battery is brought into action. The truck then con- tinues on its way as a self-contained vehi- cle. The motors are of twenty horsepower. The battery is arranged so that it can be charged with street car current when the truck is run- ning. On one charge of thebattery the truck can run for about ten miles.

���The buttonhole watch fits into a case resembling a large-sized collar button

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