jrii' 



DISCUSSION OF A KINETIC THEORY OF GRAVITATION, 



II, AND SOAIE NEW EXPERIMENTS IN 



GRAVITATION. 



(Plates V. and VI.) 



By CHARLES F. BRUSH. 

 (Read April 22, 192 t.) 



At the Minneapolis meeting of the American Association for the 

 Advancement of Science I had the honor to outhne " A Kinetic 

 Theory of Gravitation,"^ which is in substance briefly as follows: 



The ether is assumed to be endowed with vast intrinsic kinetic 

 energy in wave form of some sort capable of motive action on parti- 

 cles, atoms or molecules of matter, and propagated in every con- 

 ceivable direction so that the wave energy is isotropic. The waves 

 are of such frequency, or otherwise of such character, that they pass 

 through all bodies without obstruction other than that concerned in 

 gravitation. Distribution of the ether's energy is uniform through- 

 out the universe except as modified by the presence of matter. 



Atoms or particles are imagined to be continually bufifeted in all 

 directions by the ether waves like particles of a precipitate suspended 

 in turbulent water. 



Each particle or atom of matter is regarded as a center of 

 activity due to its energy of translation initially derived from the 

 ether. There is continual absorption and restitution of the ether's 

 energy, normally equal in amount ; but the ether is permanently 

 robbed of as much of its energy as is represented by the mean 

 kinetic energy of the particle or atom. The particle or atom thus 

 has a field of influence extending in all directions, or casts a spheri- 

 cal energy shadow, so to speak, the depth or density of the shadow 

 varying with the inverse square of distance. The energy shadow 

 of a body of matter is regarded as the sum of the shadows of its 



^Science, March 10, 1911; Nature, March 23, 1911. 



PROG. AMER. PHIL., SOC. , VOL. LX, D, DEC. 20, I92I. 



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