A STUDY OF THE SKIN AND THE KIDNEYS 241 



enlarge, and one feels all over the body a warm, healthful 

 glow. Baths should never be taken immediately after eat- 

 ing, since the blood is thereby drawn away from the organs 

 of digestion. Nor should one remain in cold water until 

 one feels a chill. If the warm reaction does not take place 

 after the bath, the latter is not beneficial, but injurious. 

 Cold baths are undoubtedly one of the best means of pro- 

 tecting the body against colds. Shower baths, however, are 

 better than a cold plunge, for they stimulate both by the 

 cool temperature of the water and by the force with which 

 it strikes the skin. 



Care of the Hair. The oil glands are most numerous in 

 the scalp, and if the skin is in a healthy condition, the 

 hair is supplied with just the proper amount of oil. If this 

 secretion dries, however, and becomes mixed with the loose 

 outer scales of the epidermis, dandruff is caused, and this 

 should be removed by vigorous brushing and shampooing. 

 Not only is the scalp cleaned in both of these ways (if 

 clean brushes and combs are used), but the friction stimu- 

 lates the circulation of the blood through the scalp, and 

 good blood is a better hair tonic than any external applica- 

 tion of the " tonsorial artist." If the oil supply is insuf- 

 ficient and the hair becomes dry, vaseline may well be used. 

 The scalp should be well dried after a bath, for moisture at 

 the roots of the hair tends to cause decomposition. 



Care of the Nails. One of the surest means of detecting 

 slovenly personal habits is by watching the care an indi- 

 vidual takes of his finger nails. An accumulation of dirt 

 beneath the nails or jagged edges caused by biting the nails 

 almost always indicate a want of good breeding. The finger 

 nails should be carefully cleaned with soap, water, and a 

 nail brush or with a nail cleaner, but never with a penknife 

 or scissors, for metal scratches the surface and makes a place 

 for the lodgment of dirt. The most convenient method of 

 cutting the nails is in a curved direction, and this gives them 

 the best appearance. The roll of epidermis about the lunula 



