It will be noticed that under such conditions Innate Intelligence is constantly working to bring about intellectual adaptation and that she is able to do so to a remarkable degree. The glands of the body are used to produce secretions which constantly bathe the tissues and keep them cool in the high temperatures, and at a proper degree of warmth in the low temperatures. The fact that the individual is indisposed to mental and physical activity in such an atmosphere is adaptative on the part of Innate. This inactivity is suggested by means of the languid feeling in order that the body will not be over-exercised and thus will not increase the amount of heat in the body; because under these circumstances the process of evaporation is interfered with and this is one of Innate’s principal means of regulating the temperature of the body.
Perspiration is an adaptation on the part of Innate, for in this way the surface of the body is kept moist and as this moisture evaporates the body is cooled; otherwise the temperature of the body would increase with every rise in the temperature of the atmosphere. Not only does this help to regulate the bodily temperature, but it keeps the surface tissue of the body soft. If there was no perspiration, the surface of the body would soon become dry, parched and hard. The skin would become scaly and would crack and become chafed.
Because of these adaptative processes it is possible for the body to be adjusted to great extremes in temperature. The body may become accustomed to extremely high temperatures even with high relative humidity, providing the change takes place gradually and sufficient time is allowed for the processes of adaptation to take place.
It is very important that the kidneys be able to perform their normal function in order that these processes of adaptation may take place. The kidneys are important not only because of the function which they perform in the excretion of poisons, but because of the function which they perform in relation to the serous circulation. This is important because of the secretions that are involved. This subject will be treated more fully under the subject of Water.
Cold Damp Air
The body quickly becomes chilled in a cold damp air because the increase in the water vapor increases the conductivity of the air for heat. It can thus be seen that the heat producing processes of the body must be increased in order to maintain the normal temperature of the body. As we know, all activity of the body requires an expenditure of energy, so if the body is exposed to a cold damp air for an abnormal length of time it will necessitate an increased expenditure of internal energy to meet the increased demands for heat and thus dissipate forces that should and would, under normal conditions, be utilized in the metabolism of the body. If the heat production is at a minimum in the body, which it may be, due to several factors such as old age, infancy, or dis-ease, this exposure to lowered temperature and high humidity will result in injury to the body.
An interference with the transmission of mental impulses to the kidneys resulting in a decrease in their functional activity may mean a retention of poisons in the body and produce a condition diagnosed as rheumatism, for example; or an interference with the serous circulation may result in the tissue cells being under-nourished. Both of these conditions will interfere with the processes of intellectual adaptation. Educationally, man may help in the adaptation by proper clothing and by giving attention to proper exercise.
Warm Dry Air
By far the most desirable air is the warm, relatively dry air; but as has already been noted, it is possible to have an atmosphere with a relative humidity that is too low. If the air is abnormally dry, and at the same time warm, there will be a great loss of body moisture due to the increased evaporation. When the loss of water from the body reaches 21% death ensues. In an experiment performed by Rubner and Lewaschew it was found that a man weighing about 127 pounds gave off about 54.1 grams of water in an hour in a temperature of 68° F. with a relative humidity of 82%; the same individual in a temperature of 68° F., but with a relative humidity of 82%, gave off only 15.3 grams.