BRUSH— KINETIC THEORY OF GRAVITATION. 45 



months ago. Study of the nature of gravitation is beset with un- 

 usual difficulties, because gravitation is ever with us and about us ; 

 it is the one universal phenomenon, and we can not escape from its 

 influence — can not obtain any outside point of view. 



In this connection I have endeavored to study the nature of a 

 magnetic field in the hope of finding something common to it and 

 gravitation; because we can largely localize a magnetic field and 

 study it. Have long regarded a magnetic field not as a static affair, 

 but alive with pulsating ethereal energy possibly akin to that of a 

 gravitation field. 



This view finally led to the thought that the very minute nega- 

 tive permeability of many substances, known as diamagnetism, may 

 also oflfer some appreciable resistance or obstacle to the gravitational 

 energy flux through such substances, and thus affect their gravita- 

 tion field. 



But what will be the nature of such modification, if any? It 

 seems highly improbable' that there can be any absorption of ethereal 

 energy by a diamagnetic substance, because this would almost cer- 

 tainly generate heat in it — it would normally be warmer than its 

 surroundings. I have carefully tested bismuth for this effect and 

 found no generation of heat. But there may be a very slight reflec- 

 tion of the ethereal wave energy from each atom or ultimate particle 

 of a diamagnetic substance, which may perhaps be regarded as a 

 scattering effect, possibly analogous to the scattering of light by a 

 faint opalescence in an otherwise transparent body. This I thought 

 should weaken the gravitation field between a diamagnetic substance 

 and a small neighboring body, whereby the attraction bet ween, them 

 would be less than between the same neighboring body and a non- 

 diamagnetic or less diamagnetic substance of the same mass as the 

 first diamagnetic substance. 



I realize that there may be no real foundation for the specula- 

 tions detailed above, though I now have much experimental evidence 

 which appears to support them ; but, if for no other reason, they 

 are important because they prompted the following experiments and 

 brought to light their surprising results. 



The first experiments were planned to detect, if possible, a dif- 



