Cold feet through irrational clothing can be caused by using garters or thick footwear with tight shoes, owing to the circulation of the blood being thus impeded in the lower extremities. It is of no use to wear the thickest woolen socks or stockings as a protection against cold feet, which should serve to retain the natural warmth of the feet, and then to prevent this warmth being given off, this latter resulting in the sensation of cold feet. But how can this thick footwear retain the heat, the generation of which it prevents by mechanically compressing the blood-vessels and thus rendering the influx of warm blood impossible? It is also useless to wear thick socks if there be no layer of air between them and the skin, which layer is the best means of retaining warmth, as mentioned in the chapter on the hygiene of the skin in connection with rational clothing. Neither the footwear nor the shoes must, therefore, be close fitting. Many people wear such tight-fitting socks or stockings, and boots or shoes, that the pattern of the socks is impressed on the feet, in which case of course it need cause no surprise if they complain of cold feet in spite of the thickness of their socks or stockings. As already mentioned in the chapter on hygienic clothing, it would be preferable to wear thin wool of the best quality and low half-shoes; when so clad we will not suffer from cold feet if we take exercise. The writer of this book wears such even in winter, in which season he puts on gaiters only when the temperature is below 20° F. On some very cold days he might feel cold in them, but then only in the morning, for after a brisk walk, or better, after a smart run (see previous chapter) the cold sensation disappears for the rest of the day. Exercise is, as a rule, the best preventative against, and the best method of treatment for, cold feet, as it is through the muscular contraction produced by walking or running that heat is generated, as explained in the previous chapter on exercise. Rubbing and massage of the feet will produce results similar to those obtained by exercise, and are still more effective if supplemented by walking. When we sit still our body will naturally cool off. It is therefore a good plan to make circular or other movements with the feet and not allow them to remain still if we feel cold in them. While residing as a guest with an elderly lady, the head of an aristocratic Dutch family, I observed her putting her feet on a silver warming utensil, in which her footman constantly burnt a little oil lamp, in order to keep her feet warm. I told her she could easily dispense with this if she would make up her mind to take exercise on foot instead of driving in her luxurious carriage, and not confine herself to merely walking from one room to another.