Page:Popular Science Monthly Volume 90.djvu/697

 Popular Science Monthly

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��A Jeweler's Daughter Wears a Potato Necklace

GATHER around, ye wealthy farmers, and gaze upon the first potato-neck- lace! You will perceive that the poor city folk are at last recognizing the true value of your commodities and assigning them a more con- spicuous place in the scheme of things.

This costly necklace was made by a Cincinnati jew- eler who experienced much difficulty in se- curing enough of the gems to complete the rare bit of jewelry.

You will observe that the largest of the potatoes js studded with diamonds. The egg suspended from it is also supplied with them.

No less than 10,000 persons were satisfied with only a look at this potato- necklace while it was on ex- hibition in the show-window. No one asked its price.

���The potato raised to the highest degree of importance and studded with "diamonds"

��Testing the Operation of Wooden Feet and Legs

FRENCH surgeons, in collaboration with manufacturers of artificial limbs, have made remarkable progress in their endeavors to provide mutilated soldiers with satisfactory substitutes for their lost legs. Some of the artificial legs devised, however, tire the user too quickly or cause

��RtCORWN^ DRUM

���The device records every movement of the foot during walking, so that it is possible to determine types of artificial legs best suited to special needs of cripples

��objectionable chafing or perhaps wounds. A Mr. Amar has recently discussed before the French Academy an ingenious invention called the dynamo-graphic side- walk, which promises to be of great ser- vice in the testing of artificial legs and in determining whether new construc- tions of such legs are free from the ordinary defects. Its pur- pose is to record accurately all movements of the foot during walking, their char- acter as well as their intensity, so that it will be possible to ascertain accurately the working of a leg and to choose a type of artificial leg best suited to the in- dividual for whom it is intended.

The apparatus con- sists chiefly of two boards (each about eight and one-half feet long and about ten inches wide) arranged side by side, but independently of each other. These boards are supported by a system of joints, springs and levers in such a manner that they will re- spond to the slightest pres- sure exerted on them, not only vertically, but longitudinally and laterally as well. These pressures will be received by the respective levers in the exact proportion of their intensity and transmitted to rubber bulbs, which in turn act by means of pneu- matic tubes on recording drums.

The two boards being independent of each other, the movements of each foot will be conveyed separately to the respect- ive levers, which resolve them into their several components and transmit the result of this analysis to the recording devices, of which there are four for each foot. It will thus be easy to read oflf the vertical pressure of the leg when it comes to rest on the board, the rearward push of the foot before throwing the body forward, and the in- ward and outward pressure it exerts. The data thus ob- tained are complemented by time measurements.

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