Hair-dyes also contain lead and other objectionable ingredients. Although less harmful than cosmetics, being generally kept away from the skin, they rob the hair of its lustre and vitality, and should be avoided. =Caution.=--Bathing, whether for cleanliness or for recreation, is a most healthful exercise, yet certain precautions are necessary. 1. Avoid bathing within two and a half hours after a meal. The sudden interruption of the process of digestion, especially by a cold bath, is apt to produce nausea. Cases of drowning, usually ascribed to cramps, have been due, in some instances, to interrupted digestion. 2. Avoid bathing when exhausted by fatigue, or from any other cause. 3. Avoid bathing when the body is cooling after perspiration. 4. Avoid bathing in stream or surf if experience proves that after being a short time in the water, there is a sense of chilliness, with numbness of the hands or feet. 5. Avoid chilling the body by sitting or standing undressed, either before going into or coming out of the water. 6. Avoid remaining too long in the water. Rub briskly and dress quickly upon the first sensation of chilliness. 7. The best time for bathing is two or three hours after breakfast. The vigorous and strong may safely take a cold bath before breakfast; the weakly and the young should not attempt it. 8. Those who are subject to dizziness or faintness, should not bathe in stream or surf without first consulting a physician. 9. Avoid a warm or hot bath, if liable to be exposed to a low temperature within two or three hours after the bath. 10. Women should carefully consult their physical condition before venturing to take a cold bath. 11. All persons suffering from organic heart disease should avoid surf bathing. PHYSICAL EXERCISE Physical exercise is necessary to the preservation of the health and the cultivation of the strength of the body. By the contraction of a muscle, the circulation of the blood is stimulated, and demand is made upon the supply of food material to replace that which has been consumed. The action of the respiratory process is accelerated, a larger quantity of air is taken into the lungs, more oxygen is absorbed by the blood, and greater tone is imparted to the system. Perspiration is also promoted, effete matters are expelled through the pores of the skin, and the general health is improved.