. Biology and human life. Biology. 384 BIOLOGY AND HUMAN LIFE In many workrooms it is necessary for the individual worker to wear an air filter over his mouth and nose. This respirator consists of a canvas cup holding a wet sponge or cloth (see Fig. 169) through which the breathed air must pass, leaving the dust behind. The gas masks worn by soldiers during the World. Fig. 169. Respirator In many industrial processes it is impracticable to remove the dust by mechanical means. The respirator is worn by the worker to filter the dust out of the air which he breathes. The sectional view shows the
. Biology and human life. Biology. 384 BIOLOGY AND HUMAN LIFE In many workrooms it is necessary for the individual worker to wear an air filter over his mouth and nose. This respirator consists of a canvas cup holding a wet sponge or cloth (see Fig. 169) through which the breathed air must pass, leaving the dust behind. The gas masks worn by soldiers during the World. Fig. 169. Respirator In many industrial processes it is impracticable to remove the dust by mechanical means. The respirator is worn by the worker to filter the dust out of the air which he breathes. The sectional view shows the valve, v, and the sponge, s, through which the air is filtered. (From photograph lent by the American Museum of Safety) War, by firemen, and sometimes by miners usually carry, in place of a mechanical filter, a chemical preparation to absorb or to counteract the gas from which they protect the wearer. 287. Fatigue. We can feel restored by sleep or rest without taking additional food. Experiments show that the human body or any other animal organism behaves, when fatigued, as though some special substance in the cells prevented their full ac- tivity. Fatigue has therefore been considered a poisoning, which. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Gruenberg, Benjamin C. (Benjamin Charles), 1875-1965. Boston, New York [etc. ] Ginn and Company
Size: 1830px × 1365px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, bookpublishe, booksubjectbiology
