As we are endeavoring in this work to give hints how to reach a ripe old age and prevent diseases which may dissipate our hopes in that direction, it is our duty to protest and to point out the dangers of such irrational heating. It seems to me, however, that in some northern countries in Europe things are not much better, especially since steam heat is becoming more and more used, as in Norway, even in the private houses. In some of these countries—Russia, for instance—cotton is put around the window panes to exclude the air, and also to absorb the moisture condensed on the inside of the double windows. In many European countries, however, fireplaces and stoves are common. The most rational method of heating, though not the most economical, is the open fireplace in England, whence the most ventilation is obtained; for the essence of the problem is to obtain warmth and fresh air at the same time. English, Scotch, and Irish are most sensitive to an overheated room, and they are probably the most healthy inhabitants of Europe, too. While a guest, some years ago, of friends in Derbyshire, I well remember that, directly the temperature rose above 65, the windows were thrown open. Americans in Europe often complain that they are not warmed at the fireplace, which only keeps the face and not the body warm. This, however, will only apply to those who only feel comfortable at a temperature of 75° F., which is distinctly unhealthy; for the open English grate can very easily produce the standard temperature of 15° R. (about 18° C.), which should not be exceeded if we want to have a healthy warmed atmosphere in our rooms. Of course such fireplaces can produce a much higher temperature, but even then the air is never so offensive as that of rooms heated by steam. It would seem, at first thought, that women can withstand cold much better than men, considering how much lighter is their dress and how much more it exposes them to cold air. We sometimes see young girls of the poorer class in such light clothing in mid-winter, standing in the streets and talking with their friends, that we men shiver at the mere idea of such clothing. Yet it is women who most need a warm room, probably because their dress is much the same indoors in mid-winter as in mid-summer. They, however, when out-of-doors wear heavy furs which entirely check the respiration of their skin; and their light clothes, when indoors, do not afford much opportunity for their skin respiration, for then there is usually no fresh air in the house, but an oppressive heat, all air ventilators being sedulously closed. It is strange how people try, by every means, to destroy their health! In warm weather we give off less warmth and do not require so much food in order to produce warmth, as the natural temperature also requires less of us; in summer, therefore, we need less nourishment.