BIOLOGY AND HEALTH 431 



Actual defects in structure or, more often, over use under poor 

 conditions, produce " eye strain " and from this result headache, 

 sleeplessness, and nervous troubles of serious nature, in addition 

 to the damage to the eye itself. Common sense in their use, im- 

 mediate rest when any feeling of fatigue is caused, and prompt 

 advice from an expert, are the only rules for the care of our 

 eyes. 



Hygiene of Bathing. Washing is primarily to remove dirt. Dirt 

 is objectionable for two reasons: it is offensive to refined people 

 and it often carries disease germs. 



Washing to " keep the pores open " is not a true reason, because 

 the skin excretes but little waste, and the pores open quickly, even 

 in the dirtiest skin, when perspiration is required for heat regula- 

 tion. 



However, there is a stronger argument for a daily cold bath, 

 because it gives the skin practice in adjusting itself to sudden 

 changes of temperature similar to those it encounters in every day 

 exposure. The cold shower or sponge bath, if followed by brisk 

 rubbing, causes the skin arteries to contract, and then expand 

 again, as evidenced by the glow of the skin. 



This is precisely what the body should do when exposed to sud- 

 den chill of any sort, and if trained by frequent cold bathing, the 

 arteries will be ready to regulate the blood supply and no cold 

 or congestion will result. 



Neither cold bathing nor swimming should be done within at 

 least an hour after meals, as the blood is needed to absorb the 

 food, and should not be diverted to the skin. The bath should 

 not be so cold, nor the swim so long continued, as to cause a per- 

 manent chill or prevent the warm reaction when the body is rubbed 

 dry. 



The cold bath is primarily a means of prevention of " colds " 

 and all that they lead to; it should be taken daily in the morning, 

 immediately upon rising. The warm bath is solely a means of 

 cleansing the skin, should not be taken every day and only just 

 before retiring, when precautions to prevent chill can be observed. 

 A very hot bath should be taken only by physician's orders. 



