4 PHYSICAL CHEMISTRY IN MEDICINE. 



connected with the existence of fluorophore radicles, 

 and in the case of antipyretics the effect of which is 

 intimately associated with their chemical constitution. 



The modern theory of solution as harmoniously 

 enlarged through VAN'T Horr's conception of the gas- 

 like condition of the dissolved particles, and ARRHENIUS'S 

 teaching that electrolytes salts, acids, and bases dis- 

 sociate upon solution into their constituent ions, has 

 also found extensive scientific application to many 

 subjects including medicine. 



Following the establishment of these fundamental 

 facts physical chemistry has developed as an independent 

 science with numerous methods of experiment peculiar 

 to itself and adapted to its own special purposes. 



Medicine has at no time denied its dependence upon 

 advances in the exact sciences, and so it is not strange 

 to find that with new ideas in physics there have come 

 corresponding periods of discovery in medicine. But 

 the application of newly discovered facts in physics 

 to medical problems for the solution of which they were 

 never intended has as a rule brought it to pass that every 

 era of progress has been followed by one of disappoint- 

 ment, a period characterized by an overgrowth of specu- 

 lation and hypothesis. 



The great development of mechanics in the seventeenth 

 century associated with the names of STEVIN, GALILEI, 

 KEPLER, DESCARTES, HUYGHENS, and many others fruc- 

 tified the epoch of the iatro-physicists whose accomplish- 

 ments as evidenced by their work on the mechanics of 

 joints and the development of Harvey's teaching of the 

 circulation have lasted into modern times. But even 



