This section is from the book "The Hygienic System: Fasting And Sun Bathing", by Herbert M. Shelton. Also available from Amazon: The Hygienic System Vol III Fasting and Sun Bathing.
Efforts are made in many quarters to convince everyone that the sunbath is a complicated and extremely hazardous procedure that can be applied only by a technically trained man from the laboratory, or a physician. One is almost certain to get the impression, when reading the average book on sun-bathing, that the sun-bath is very difficult, and also very dangerous. There are so many precautions enumerated, so many ceremonial details to be attended to, and so many times and conditions when the sun-bath should be avoided, that one is very likely to give up in disgust and forget the sun-bath.
Much of this is pretense with a commercial basis. Anyone with sense enough to eat, or sleep, or exercise, or breathe pure air, can take a sun-bath. It is as natural as any of these things and equally as simple. The ritual employed by Rollier and other physicians is not essential. These begin by exposing the foot for a few days, then one leg, then both legs, then one thigh, then the abdomen, then the chest, and lastly the back. All of this is needless ceremonial. It is my conviction that Rollier is over-cautious in beginning sun bathing and over-does the process after the patient has acquired a good coat of tan.
A few simple precautions must be observed in sun-bathing, and anyone of average intelligence may understand and apply these. The following precautions are especially necessary to those who have never taken sunbaths.