164 THERAPEUTICS AND PHARMACOLOGY 



connection between the effect of common alcohol and of glycerine 

 can be established. 



In general we must confess, however, that we cannot as yet 

 speak of a relation between constitution and effect, because what 

 we call effect must be regarded as an influence on the different 

 functions. Even if we consider the apparently simple mechan- 

 ism of sleep, we must remember that it may be induced by an in- 

 fluence on the brain, or equally well by an action on the peri- 

 phery. We cannot here enter into a physiological analysis of the 

 processes taking place in the organism, but, as the above example 

 shows, the most diverse parts of the system may be affected, so as 

 to produce a similar result. Moreover, the different hypnotics, 

 although fulfilling the same purpose, have an entirely different 

 composition. On the other hand, when investigating the action 

 of chemical substances we may always expect new results to be- 

 come manifest by chance, for when Baumann was studying the 

 effects of sulfonal it had never occurred to him that this body might 

 possess soporific powers. We can best see the prominent part played 

 here by chance in the introduction of salicylic acid into therapeu- 

 tics. After Kolbe had succeeded in synthetically producing this 

 acid, which is normally contained in the bark of the willow, he 

 thought that it would exhibit disinfecting properties within the 

 system by its decomposition. This decomposition does not, how- 

 ever, occur. Yet Kolbe's idea has led to the clinical application 

 of this substance, and the valuable results obtained by Strieker 

 from the use of salicylic acid in acute articular rheumatism, al- 

 though it is not by any means a specific, have stimulated to con- 

 tinuous researches, most fertile for therapeutics, upon the various 

 salicylic preparations. 



It is not impossible that, starting from this small therapeutic 

 field, the indications for the use of salicylic preparations may be 

 greatly extended. 



Even though the constitution of a chemical body gives us no 

 firm basis for pharmacodynamic investigations, we can yet de- 

 rive the most varied hypotheses from it. In pharmacodynamic 

 research we may uphold the same principle which Claude Berhard 

 expresses, namely, that by promulgating an hypothesis we are led 

 on to experimental research, the solution of which may be of the 

 greatest importance. G. Gore expresses his opinion in much the 

 same way : 



"A discoverer is a tester of scientific ideas; he must not only 

 be able to imagine likely hypotheses, and to select suitable ones 

 for investigation, but, as hypotheses may be true or untrue, he 

 must also be competent to invent appropriate experiments for testing 

 them, and to devise the requisite apparatus and arrangements." 



