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
Careful in- vestigation
it was noth-
i n g more
c 1 e v e/ 1 y -
A descrip- tion of the
of how it
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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