This doctrine is corroborated by the findings in regard to infections. Through fever the organism is freed from micro-organisms which may have forced their way in. Fever operates like fire, destroying the contagious matter. After this is done the remnants are excreted through intense and extremely offensive perspiration. Experiments have taught us that the growth and the resisting power of many microbes decrease if the temperature of the body rises, but 1.8 to 3.6 degrees above normal. It is also a remarkable fact that in every disease where bacteria are found, there is a special type of fever, which takes its course in such strict accordance with its law, that the physician is thereby able to determine the nature of the disease. While the degree of temperature is decisive in regard to the life of micro-organisms, the height of the temperature does not, in itself, constitute a criterion of the gravity of danger. It is the duty of the physician to fight the fever, since the patient may succumb to a high temperature, as to a low one. In order to gauge the situation accurately it is necessary to regard fever, not as a disease, but as what it really is in essence: a symptom which accompanies the greatest variety of the processes of disease,--symptom of the most variable significance in various cases. It must be fought like other symptoms, such as vomiting, coughing, pains and diarrhoea; namely, in a general way--provided only that it is not a manifestation of the healing tendency of the organism. In decreasing the fever, we moderate the excitement of the nerves, remove the numbness, secure calmness, refreshment and sleep, and defend the patient against threatening manifestations of disease. Very often it is not a case of treating the fever, but of dealing with the disease which causes the fever. We must consequently not be guided by the thermometer but by the condition of the nervous system. Two conditions must be observed in treating fever according to the rules of biology. In the first place, the treatment of febrile disease must not be carried on in accordance with general principles, but individually, according to the nature of the disease in each particular case. In the second place, it is necessary that the antipyretic treatment, to reduce the fever, should not be foreign to the organism and should not be such as is not measurable in degrees as to its effects, or has any unpleasant accompanying effects or after-effects. Only the biological system of healing responds to these demands. Only cognate physical forces, in affinity with the human organism according to biological laws, can influence vital occurrences with the hope of success and without the danger of unfavorable accompanying effects and consequences. Only physical remedies and treatments permit of adequate gradations such as will appeal to the power of reaction of the organism.