BRUSH— KINETIC THEORY OF GRAVITATION. 51 



netism is not simply a manifestation of negative magnetism (and 

 this view is supported by the fact that diamagnetism is not affected 

 by varying strength of magnetic field), but is an inherent attribute, 

 in varying degree, of many kinds of matter, often more or less 

 masked by paramagnetic qualities. 



It is also interesting to note the low atomic weight and small 

 density of aluminum at one end of the scale of attractions, and 

 bismuth with its very high atomic weight and large density at the 

 other end. 



It seems needless to say that the line of investigation indicated 

 by the foregoing experiments is but barely begun. It is proposed to 

 try many other metals, as well as alloys and chemical compounds, in 

 the hope of finding some general law embracing all. 



If such further experimentation confirms, in general, the findings 

 already made, and I have yet found no reason to doubt that this 

 will be the case, the scientific possibilities of the discovery are rather 

 bewildering. It may mean, among many things, that we shall have 

 to revise our notions of atomic weight values ; that the second part 

 of Newton's law of gravitation is not general in its application, and 

 that if Professor Boys and others had used zinc or tin or bismuth 

 for their large attracting spheres, instead of lead, their findings for 

 the gravitation constant and mean density of the earth would have 

 been materially dififerent, though still erroneous. 



As soon as the above-described experiments had proceeded far 

 enough to afiford reasonable assurance that the eiifects observed were 

 not spurious, though very much larger than looked for, I planned 

 and began work on some pendulum experiments in the hope of again 

 showing that weight and mass are not related in so simple a manner 

 as heretofore supposed. 



Of course weight is only an accidental attribute of mass and varies 

 enormously in different localities, as on the sun, the earth, the moon 

 and in interstellar space; while mass remains constant everywhere. 

 But relative weight has always been taken as a true measure of 

 relative mass in the same locality. The foregoing experiments seem 

 to refute this ; hence the pendulum experiments were undertaken for 

 proof or further refutation. 



