Lessons on elementary hygiene and sanitation : with special reference to the tropics / by W.T. Prout.

  • Prout, W. T. (William Thomas), 1862-
Date:
1905
Catalogue details

Licence: In copyright

Credit: Lessons on elementary hygiene and sanitation : with special reference to the tropics / by W.T. Prout. Source: Wellcome Collection.

    177/186 (page 155)
    LECTURE XIV. CLOTHING. Clothing is required for several purposes, ist, to protect the body from injury; 2nd, to preserve the temperature of the body ; and 3rd, for purposes of ornament. Of these the most important is that connected with tem- perature. The value of a clothing material depends upon its conducting properties with regard to heat. A good conductor is a substance through which heat travels rapidly, for example, metal. If we heat one end of a bar of iron, we find that the other end gets very hot too. Iron, then, is a good conductor. If on the other hand we heat, or even burn the end of a piece of wood, the other end will not readily get hot. Wood is a bad conductor. And similarly, the materials ol which clothing is composed, vary much as to their powers of conducting heat, and advantage is taken of this to keep our- selves warm or cool. Now in this country we are favoured by nature, for we have not a winter with its snow and frost, to contend with, and consequently our bodies do not require so much protection. In cold countries, where the temperature of the air is much below that of the body, clothing is worn to' keep us warm ; in hot countries it is in addition, a protection against the rays of the sun, and helps to keep us cool. The body loses heat in several ways, by the skin, by respiration, and by the excreta. The skin is the most important, heat being lost by radiation from the surface of the body, and by evaporation. The moisture of the skin—the sensible and insensible perspira- tion—evaporates, and in doing so absorbs a large amount of heat from the body. That is why we are so apt to get chills, if we stand in a cool breeze when we have been perspiring, without being properly protected. Clothing then should be of such a nature as to absorb perspiration. Clothing should be light, and this is especially the case in this country, where heavy clothes produce excessive per- spiration. There is a tendency among civilised natives to wear too much clothing, and sometimes when I have had to examine a man, I have seen him take off a heavy tweed coat, a waist- coat, a heavy shirt, and then a thick undervest or two, which is far too much for a tropical climate. A thin flannel shirt, a coat, and perhaps a light waistcoat are quite enough.