This section of the book is from "The Complete Herbalist" by Dr. O. Phelps Brown. Also available from Amazon: The Complete Herbalist: The People Their Own Physicians By The Use Of Nature's Remedies.
Were all to follow the natural laws of their organization in respect to eating, drinking, clothing, exercise, and temperature, an occasional bath or washing would be sufficient; but as the laws of life and health are transgressed in a thousand ways, the sum total of all the unphysiological habits of civilized life is a condition of body characterized by deficient external circulation, capillary obstruction, and internal congestion or engorgement. To counteract this morbid condition of the system, bathing of the whole body, on regular occasions, cannot, or should not, be omitted. For hygienic purposes, the particular process is merely a matter of convenience. You may bathe in a river if you like, or may employ the shower-bath; but these modes are no more beneficial than the towel or sponge-bath. After the ablution, in whatever manner performed, care should be taken to thoroughly rub the body with a crash towel. The best time for such purification of the body is on rising from bed in the morning. The temperature of the water should be adapted to suit different circumstances of constitutional health and disease. Cold or cool baths are best for those in robust health; but those who are deficient in blood, or have a low vitality, should use tepid water. Extremely feeble persons should commence with warm water, and gradually reduce the temperature as reaction improves. Sponging the body with spirits or vinegar may prove highly beneficial in many cases of debility, where water would be injurious. Excessive bathing tends to make the skin harsh and scaly by diluting the secretions of the sebaceous glands, the oil of which is intended to be regularly and naturally poured out to the surface of the skin in order to keep it smooth, glossy, and soft. Bathe as often as may be necessary to keep the skin clean, and you will then have fulfilled the requirements of hygienic bathing.