Page:Popular Science Monthly Volume 26.djvu/249

Rh natural moisture is not allowed to dry. The man is in an atmosphere, now hot and moist, now cold and moist. His clothing can not adjust itself to the changes of temperature so well as his skin once could. He gets wet in a rain, and is chilled by the drenched clothing which does not dry as his skin would have done. He begins to experience the phenomenon of taking cold. The multiform ailments which thus originate begin to beset him. The lungs especially are apt to suffer, and his health is seriously broken. Once he had a thick skin, the perfect clothing which Nature gives her animals. Now, a thinner, more sensitive one grows under the habiliments that mark the new social order. This is not merely theory. The New-Zealanders themselves ascribe their physical decay in part to their assumption of clothing. Mr. Nordhoff, in his book on the Sandwich Islands, also alludes to this as one possible cause of the decay of that people. In the case of the African slaves the element of clothing is of less consequence. For here the people have been removed from their native climate to one which necessitates some clothing on grounds of actual comfort. Morover,Moreover, [sic] they were not as a rule obliged to wear more than the real demands of the climate required; so that there was not even a temporary decrease of their numbers from this cause. But in tropical peoples, and in all others where the innovation in the matter of dress is independent of any real physical requirements, theory and fact agree in ascribing a malign influence to the change. In the ancient myth, Hercules untiringly endured his mighty labors, and was victorious in all his sturdy conflicts with opposing forces; but, at last, the poisoned robe of Nessus brought him to his death. So to many a child of Nature has the garb of civilization proved an envenomed mantle, consuming its wearer.

Closely connected with the subject of clothing is that of food; for physiology shows us a reciprocal relation between them. The life of a starving animal can be prolonged by retaining his warmth, or, in other words, by clothing him; and, conversely, an increase of clothing diminishes the consumption of food. When our newly civilized barbarian puts on clothing which the temperature of his climate does not require, he must lower his diet in a corresponding degree. The extent of this influence may be appreciated from a brief view of the physiology of nutrition. The non-nitrogenous articles of food and the non-nitrogenous modicum which remains after the splitting up of the nitrogenous (proteid) foods furnish the energy of the body. This is estimated in the average man at one million metre-kilogrammes daily; the force required to raise one kilogramme in weight one metre in height being the unit of force. Now, of this force, 150,000 metre-kilogrammes are expended in muscular work, and the remainder, four fifths or more, are required to maintain the animal heat. But three fourths of the entire heat expenditure is made by radiation and