Popular Science Monthly 



Shoot or Stab This Dummy, and 

 You'll Be Blown Up 



""DOOBY traps," as the. British call them, 

 1) are dummy soldiers containing a 



large amount of high explosive. They are 



death traps set by the Germans for their 



enemies. Scientifically and painstakingly 



constructed, 



the dummy 



shown would 



have blown 



to pieces 



anyone who 



touched it. 



Fortunately 



the British 



"smelled a 



rat." They 



would not 



touch it. 



Careful in- 

 vestigation 



proved that 



it was noth- 



i n g more 



than a 



c 1 e v e/ 1 y - 



contrived 



bomb. 



A descrip- 

 tion of the 



dummy 



which 



reached this 



country 



does not 



contain an 



explanation 



of how it 



could have 



been ex- 

 ploded. The 



British re- 

 ports have 



not de- 

 scribed its internal organism. Conjectures 



are many. Some believe that a fall 



resulting from the slightest jolt would 



have caused the explosion. 



The death-trap left by the Germans in a locality they were 

 compelled to evacuate. The figure contained high explosives 



555 



The By-Products of the Grapefruit 

 Obtained from the Culls 



WHEN the fruit-grower has marketed 

 his finest and best specimens of 

 grapefruit there are likely to remain many 

 inferior specimens which would be wasted 

 unless utilized to obtain the by-products. 



These by- 

 products 

 have been 

 found to be 

 numerous. 

 Citric acid is 

 obtained in 

 great quan- 

 tities from 

 the culls, es- 

 p e c i a 1 1 y 

 from the 

 early winter 

 fruit. Sugar 

 is obtained 

 at the rate 

 of about 4.4 

 per cent in 

 the early 

 winter fruit 

 and 8.5 per 

 cent in the 

 spring fruit. 

 The peel 

 yields about 

 2.1 per cent 

 of recover- 

 able oil. A 

 good yield of 

 pectin is also 

 obtained 

 from the 

 skins. This 

 is a grayish- 

 yellow flaky 

 mass re- 

 sembling 

 sugar in 

 appearance which stiffens on standing in 

 water to a clear, tasteless jelly and is 

 used as the basis of many kinds of 

 fruit desserts. 



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