Page:Popular Science Monthly Volume 89.djvu/741

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��"Sandwich-Man" Clad in an In^iitation Bullet THIS is not a new type of cli\iiig suit, or a patent respirator used to repel a gas attack, or a new- fangled barrel for the fellow who has lost his clothes. It is merely an advertising stunt, a sort of super-sand- wich-man, to attract the eyes of the curious. On the back of the device are letters which describe a product on the market. The conical headpiece resembles alumi- num, and a circular oijening is cut in it just large enough for the wearer to sec his wa>- ahead and breathe comfort- ably. The shorter the w'earer the more mysterious becomes the appearance of the powderless bullet. If no part of the bod\- except the feet are visible as the bullet wends its way doAvn the avenue, it is pretty sure to be the cynosure of thousands of wondering eyes.

���The newest recruit to the peaceful army of "sandwich-men"

��Kneading Potter's Clay with the Bare Feet

THE illustration shows a man sub duing a pile of recal- citrant clay. If it were possible to use his hands in kneading the clay the man w' o u 1 d no doubt prefer to do so, but without a mechanical knead- er he is obliged to use his feet, which method has been used for many cen- turies in the old world.

It requires no little amount of strength to knead clay, and when the feet are emplo\'ed the weight of the bodv is utilized.

���A modern potter kneading clay with his feet, as it was done in the days of Cleopatra

��Why Gold Pieces Are Always "Doctored"

WH\' <lon"t jewelers melt up Sio and S20 gold pieces in order to use the metal in the manufacture of gold jewelry .■" Indeed, gold pieces were used some forty years ago by enterprising jewelers and with success, too — until the practice was stopped in a very novel but effective way. In those days jewelers bought enough Sio and S20 gold pieces for the work in hand. The gold was melted, the necessary alloys were added, and all manner of fine Etruscan work was turned out.

It was not long, however, before the Government be- gan to wonder what was becoming of its gold pieces. The officials knew the people were not hoarding gold, so a quiet investigation took place. It w'as then discovered that the makers of gold jewelry w-ere to blame. Having found the cause, it was not difficult for the officials to find a cure. They did it by "peppering" the coins with iridium. Resembling black emery in the crude state, iridium requires a heat of 3,542 degrees Fah- renheit to melt it. Gold, on the other hand, can be melt- ed at 1,913 degrees Fahrenheit. It is easy to see, then, how the unsuspecting jeweler, melting up his gold pieces at the temperature required, got a large number of unnielt- ed specks of iridium in his metal when it cooled.

You can imagine his dismay when his analysis and deductions re- vealed that he had been trapped.

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