398 PHYSIOLOGY 



conditions which apparently do not agree with some established law, 

 he does not transfer these conditions to a pathologist in physics for 

 further investigation. On the contrary, he is only too glad to have 

 such an opportunity; it usually leads to an elucidation of the old law, 

 or, still better, an entirely new law might be discovered. When Kirch- 

 hoff was surprised by the apparently contradictory fact that by the 

 addition of the yellow light of sodium to the sunlight the dark D- 

 lines in the spectrum, instead of becoming lighter, became still darker, 

 he did not turn away from the problem. On the contrary, he was glad 

 of this opportunity; in fact, as he stated once, he was longing to meet 

 such a complete contradiction. The result was the establishment of 

 the law of the proportion between emission and absorption of light 

 and the creation of the nearly new science of spectral analysis. Or, to 

 quote a more recent instance, the exceptions to van 't Hoff's law of 

 osmosis which were met with in salt solutions and which had been 

 displayed by some as a proof against the validity of that law, served 

 Arrhenius as a basis for the establishment of the far-reaching law of 

 electrolytic dissociation. It is totally different, however, with physi- 

 ology. Its domain is, as we saw above, the study of the functional 

 side of living phenomena. Here, however, we find the artificial and 

 unsound distinction between normal and abnormal functional phe- 

 nomena. Physiology set up some laws; and if conditions appear 

 which do not fit in with these laws, physiology declines to deal with 

 them; it refers you to medicine. Are the laws governing the vital 

 functions under pathological conditions actually different from those 

 controlling the functions in health? Certainly not. The laws which 

 physiology establishes must be capable of covering the functional 

 phenomena in all conditions of life. The apparent exceptions in dis- 

 ease should serve in physiology, as in physics, to unravel the real 

 nature of the laws governing the functions of living phenomena, 

 whether they occur in health or in sickness. For instance, the pro- 

 cesses occurring while the body is in a state of fever should give a clue 

 to the understanding of the mechanism of the constancy of the ele- 

 vated temperature of warm-blooded animals. Or the conditions pre- 

 vailing when urine contains albumin should be seized as a means of 

 studying the remarkable phenomenon in the normal urinary secretion, 

 namely, that of all the endothelial cells of the body the kidney endo- 

 thelia alone do not permit normally the passage of albumin. Or the 

 conditions of the blood and the lung tissues in pneumonia could serve 

 as an aid in studying the factors concerned in the formation of fibrin. 

 And so on and so on in many thousand instances of daily occurrence. 

 Some very important discoveries in physiology were thus recently 

 brought to light through medical experience and by medical men, 

 with hardly any aid from physiology. The anatomy of the cases of 

 myxoeclema and cretinism and the results of the complete removal of 



