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KEEPING RATS FROM GEHING ASHORE — OR ABOARD 



Ships plying between ports in which there are infected rats and other ports receive 

 special attention from health officers. Metal shields are used to prevent rats infected 

 with the plague from getting off the boats, or from getting aboard in plague areas. 

 In addition, of course, pains are taken to destroy rats on ships, and to prevent their 

 breeding 



scurvy, beriberi, rickets, and other diseases are due to the lack of specific vita- 

 mins in the diet. 



Modern industry and modern city living have brought into our environ- 

 ment physical and chemical changes that often disturb us. Various dusts and 

 fumes affect the breathing organs, or introduce into the body substances that 

 modify the metabolism. The materials handled by workers affect the skin, 

 the nerve-endings, and perhaps deeper tissues and organs. Lighting condi- 

 tions, unusual or loud sounds, affect the inner co-ordination of processes, even 

 when we are not aware of them. Eyestrain has been found to result in nervous 

 tension which in turn influences the digestive process and possibly other proc- 

 esses by way of the autonomic nervous system and the endocrines. 



General fatigue has long been recognized to be an outcome of excessive exer- 



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