Page:Popular Science Monthly Volume 91.djvu/571

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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


the dummy

shown would

have blown

to pieces

anyone who

touched it.


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 -



A descrip- tion of the



reached this


does not

contain an


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


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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