QUALITATIVE AND QUANTITATIVE. 215 



of pitch and quality of tone are reduced to a dif- 

 ference in the fibres of the nerves receiving 

 the sensation, and for each individual fibre of the 

 nerve there remains only the quantitative differ- 

 ence in the amount of excitement." * 



It would seem, on investigation, that this as- 

 sumption will give " not only a very simple and 

 perfectly consistent explanation of all optical and 

 auditory phenomena, but also of the phenomena 

 peculiar to each individual organ in the human 

 system." 



The organs " belonging to the body, the heart, 

 intestines, ear, eye, and brain, &c., as well as the 

 body itself, are individual. 



Their individuality consists in the peculiar 

 arrangements by means of which their distinc- 

 tive functions are performed. There are not 

 only nervous but also muscular arrangements, 

 whose contractility is of vital importance in pro- 

 ducing the various motions. The nervous force 

 predominates if delicacy, the muscular if strength, 

 is to be produced. These varying combinations 

 of nerve and muscle are molecular arrangements. 



All molecules are electro-magnetic. As the 

 human system is composed of molecules, the 

 body itself and its molecular groupings into dis- 

 tinctive organs must also be electro-magnetic. 

 As each molecule serves as an electric machine 

 for developing a peculiar reaction, so each kind 



l Helmholtz's Sensations of Tone. 



