Page:Popular Science Monthly Volume 91.djvu/37

 Places Where Gas Masks Are Necessary

��A gas mask worn by the photographer enables him to take a picture of the man who is shown at left below repairing a leak in an ammonia tank. Dur- ing the time the photograph was taken choking fumes of ammonia were escap- ing in great volume from the tank, which is situated in a cold storage plant

��Photo? © Kadel and Herbi

����Repairing the ammonia tank, a task made safer through the use of the gas mask. The cylinder below the mask contains chemi- cals which absorb all of the poisonous fumes and allow only pure air to reach the lungs

��A chemist experimenting with a dangerous combination of chemicals which give off poi- sonous fumes. With the gas mask pro- tecting his nostrils, he is able to approach close enough to his work to watch it intently

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