Popular Science Monihhf 



913 



It is hard to realize that this remarkably life-like Dutch village scene is all sham and 

 deceiving trickery, built to serve only a brief while until the camera has caught it 



to assume the appearance of paving 

 stones. The roofs of the houses are made 

 of tiling and shingles laid on loosely 

 and easily removed. For next week this 

 village may be in Siberia, with a roof of 

 ice, and the canal will be the road before 

 the dismal village inn ! 



What the Twenty-Dollar Gold 

 Piece Has Been Through 



THE twenty-dollar gold piece has had 

 an interesting career. Jewelers melt- 

 ed it for their fine gold work, some forty 

 years ago, and were very successful until 

 the Government experts discovered the 

 practice and stopped it in short order by 

 "peppering" the gold with iridium. Fol- 

 lowing this, unscrupulous persons at- 

 tempted to gather scrap gold by "sweat- 

 ing," or placing a number of coins in a 

 bag and then shaking them violently, 

 thus obtaining tiny particles of gold by 

 friction. After these coins had been put 

 through the "sweating" process it was 



an easy matter to pass them on unsus- 

 pecting tradesmen and banks, provided, 

 of course, that the victims did not weigh 

 the coin. The amount of gold scrap 

 obtained by the "sweating" process was so 

 small that the bags had to be burned to 

 recover it. 



Another way was to "strip" a coin by 

 putting it into an electro-chemical bath, 

 getting thereby a slight residue of gold 

 on a copper plate, which was afterward 

 melted and the metals separated. Be- 

 cause this method discolored the gold 

 it was not very popular. One of the most 

 successful schemes, however, was the 

 use of a specially prepared male and fe- 

 male die. The diameter of the die was 

 about one one-thousandth of an inch 

 smaller than the diameter of the coin. 

 It was so made that after the resultant 

 rim of metal was cut off the milled edges 

 remained. From a single $20 coin the 

 gold thus obtained was worth about fifty 

 cents, and the coin, to all appearances, 

 had not been tampered with. 



