HEALTH HABITS 



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sleep an important factor in the health of the nervous system of 

 growing children. Ten hours of sleep should be allowed for a child, 

 and eight hours for an adult. At this time the brain cells have 

 opportunity to rest and store food and energy for their working 

 period. 



Sleep is one way in which all the cells in the body, and particularly 

 those of the nervous system, get their rest. The nervous system, 

 by far the most delicate and hardest-worked set of tissues in the 

 body, needs rest more than do other tissues, for much of its work 

 directing the body ends only with sleep or unconsciousness. The 

 afternoon nap, snatched by the brain w^orker, gives him renewed 

 energy for his evening's work. It is not hard application to a 

 task that wearies the brain ; it is continuous work without rest. 



Health Habits for the Sense Organs. — Overstimulation of any 

 of the sense organs is a bad thing. The taste cells may be over- 

 stimulated with too much seasoning in food, with tobacco or alco- 

 hol. The ear may be ove'^stimulated by loud noises ; the eye by 

 too bright light ; the olfactory cells by too heavy odors. 



The most frequent habits of abuse of the eyes are using them in 

 a dull or flickering light or in too bright a light with a glare on the 

 page, when reading. Light should come over the left shoulder 

 We should avoid looking directly into the source of light. 



Look at either of these figures with one eye closed. If part of the Hnes appear 

 blurred, you have astigmatism and should consult an oculist. 



The eyes are also subject to infection and injury from dust, cin- 

 ders, flying bits of metal, etc. Certain trades in the past have 

 taken a high toll of eye injuries, although now workers are protected 

 by proper goggles. In case of soreness or irritation place a drop 



H. NEW CrV. BIOL. — 15 



