ARTICLE VI. 



ON THE NUMERICAL RELATIONS OF GRAVITY AND MAGNETISM. 



BY PLINY BAULK CHASE, M.A., S.P.A.S. 



(Magellanic Premium Awarded, December 16, 1864.] 



The dependence of magnetism upon currents of some kind, has long been generally 

 admitted ; but it has usually been assumed that these currents are of a peculiar nature, 

 and that they require for their development the existence of a magnetic fluid or aether, 

 distinct in its properties from any other form of matter. 



A current presupposes an impelling force, competent to produce a tendency of particles 

 toward some particular point, and an inert or resisting medium upon or against which the 

 force is exerted. Motion, whenever it occurs, is always in the direction of least resist- 

 ance, — a direction that can be calculated by mechanical laws, when all the determining 

 data are known. 



That all forces are in some manner mutually connected, so that gravity and magnetism 

 may be more or less convertible into each other, like light, heat, and electricity, was early 

 suspected by Professor Faraday ;* but, on account of the impossibility of escaping from 

 the influence of terrestrial magnetism, all attempts to demonstrate their convertibility 

 have been hitherto unavailing. I have elsewhere suggested, as a possible test experi- 

 ment,f " centrifugal force, so applied as alternately to assist and oppose the effects of 

 gravity, as in large fly-wheels revolving with various degrees of rapidity." An arrange- 

 ment of this kind is presented by the earth in its daily rotation, its centrifugal force being 

 alternately added and opposed to the influence of solar attraction ; and, from an examina- 

 tion of various recorded observations, I have deduced the following propositions : 



* Phil. Mag. [4] 1, 68. My own belief in the correlation of motion, light, attraction, heat, electricity, and 

 vitality, was first publicly announced in a lecture delivered before the Lyceums of Worcester and Lynn, Massa- 

 chusetts, in the winter of 1844-5. Luring the two previous years, Mayer, Colding, Joule, and Grove, had pub- 

 lished their first papers ; but I am not aware that any report of their views had reached America. 



If we regard mobility under its three necessary relations, wc may, perhaps, advantageously group the elementary 

 forces under the throe heads of — 



1. Influx : Gravitation, Affinity, Cohesion. 



2. Immanence : Polarity, Electricity, Vitality. 



3. Emission : Light, Heat, Actinism, 

 -j- Proe. Am. Phil. Soc. v. ix, p. 856. 



