1881.1 ^^'^ [Chase. 



evidences in times of planetary revolution ; Faraday strove in vain to 

 reconcile the law of gravitation with, the theory of conservation of energy ; 

 "Weber and Kohlrausch introduced a general kinetic notation and found 

 the importance of the velocity of light in electrical phenomena ; Faraday 

 discovered the magnetic influence upon light and Sir William Thomson 

 stated that "the explanation of all phenomena of electromagnetic attrac- 

 tion or repulsion, and of electromagnetic induction is to be looked for 

 simply in the inertia and pressure of the matter of which the motions 

 constitute heat ;" Maxwell* considered magnetic force as the effect of the 

 centrifugal force of vortices, electromagnetic induction as the effect of the 

 forces called into play when the velocity of the vortices is changing, elec- 

 tromotive force as arising from the stress on the connecting mechanism, 

 and electric displacement as arising from the elastic yielding of the con- 

 necting mechanism. 



64. Beclaination. 



In 1863, I began a systematic series of investigations, in the hope of 

 'aerifying, hy numerical measurements, some of the supposed consequences 

 which seemed to flow from the foregoing researches and hypotheses, and 

 of finding new dues to the values and relations of the fundamental ele- 

 ments of physical energy. The division of forces into attractive and repul- 

 sive, as well as the equality of action and reaction led me to the study of 

 the laws of elasticity and their influence on undulatory and cyclical mo- 

 tions. In my first paperf I called attention to the effects of cyclically 

 alternating acceleration and retardation during rotation or revolution. 

 In the course of the seven following months, I pointed out various rela- 

 tions which seemed to have been previously unnoticed, between heat, 

 gravitation, electricity and magnetism, showing that many of the phe- 

 nomena could be imitated and explained by the mechanical propagation of 

 vibrations. The tendencies to equilibrium betAveen graAatating pressui'e 

 and sethereal elasticity, the necessary production of continual oscillations 

 by opposing forces, the possibility of accounting for gravitation, electricity 

 and magnetism by such oscillations moving with the rapidity of light, 

 were all discussed during this period. 



65. Musical Rhythm. 



Fourier (Note 33) seems, to have first given a mathematical demonstra- 

 tion of the necessity that cyclical motions should be also rhythmical. If 

 the luminiferous aether is anything more than a hypothesis, which helps to 

 explain an indefinite variety of phenomena, the tendency to the produc- 

 tion of harmonic nodes in elastic media must greatly multiply the rhyth- 

 mical manifestations, both cosmical and molecular. Some of those har- 

 monies have long been known, their discoA^ery having been apparently the 

 result of accident, or of a happy guess. The number which will hereafter 

 be made known will depend, in large measure, on the skill with which 



* Electricity and Magnetism, ii, 417. 

 t Proc. Am. Phil. Soc, ix, 2S5, Dec. 1863. 



PROC. AMER. PHILOS. SOC. XIX. 109. 3f. PRIXTED JULY 16, 1881. 



