Page:Popular Science Monthly Volume 88.djvu/924

 896

��Popular Science Monthly

���The "Torpedo Kid" was modeled after a falling drop of oil

An Electric Automobile Built Like a Drop of Oil

OUR present day pear-shaped racing automobiles are all distant cousins, so to speak, of the "Torpedo Kid," a car designed by Walter C. Baker, the creator of the first American-made electric. In a dash at Ormonde Beach, Florida, some years ago, it did a mile in 56 seconds, establishing a world's record for speed at that time.

Oddly enough Mr. Baker came to be the originator of the first pear or cigar- shaped racer by studying the shape of a drop of oil as it fell through the air. He observed that the drop, while falling, was not round but took the form of an ellipse. In short time he arrived at the conclusion that a solid body of the same shape as the drop of oil, if cut in two and built low to the ground, would offer the least possible wind resistance. He followed out this theory in the construc- tion of the "Torpedo Kid," and its initial record of a mile in 56 seconds proved that Mr. Baker was right.

Other automobile manufacturers were quick to see the advantages of the constructional features embodied in the "Torpedo Kid," with the result that pear-shaped racers, electrically and gas- oline-propelled, began to dot the courses of our race tracks. For a while the electric racers held their own against the others, but the gasoline engine improved so rapidly that before long the electric racer was as scarce as it was before the heyday of the "Torpedo Kid." However, Mr. Baker has built a larger car along the same lines as his speediest electric, and it is said to have made one hundred and twenty miles an hour. A few years ago it was entered in some

��races in France but before it could give account of itself, it got beyond the control of the driver and ran amuck, injuring several bystanders.

Signaling Three Hundred Miles

A PORTABLE electric signal-light which, although operated by dry- cell batteries, gives two hundred and fifty thousand candlepower, has been designed and constructed by E. G. Fisher, chief of the instrument division of the United States Coast and Geo- detic Survey. It is to be used during the summer in the mountainous regions of Idaho and Oregon on primary triangula- tion where the distance between stations is frequently as much as one hundred miles. No larger than the ordinary automobile head-light, the packed ap- paratus weighs about twenty-three pounds. Under ideal atmospheric condi- tions the light will be visible through a telescope of ordinary power for a distance of two hundred and fifty to three hundred miles.

The great power of the light is due to a new type of tungsten filament designed by Mr. Fisher. The filament is concen- trated so aS to confine the light to as small a point as possible — very much as in the gas-filled lamps now used for street- lighting. There are two tiny coils of filament about one tenth of an inch in height and one thirty-second of an inch in diameter, connected by a loop at the top. The glass bulb is about two inches in diameter.

The light is about one hundred and seventy times more powerful than that given by the acetylene signal lamps now being used by the survey.

���A specially constructed tungsten filament enables this lamp to throw its rays a dis- tance of three hundred miles

�� �