oOO Prof. J. Lovering on the Mathematical and 



have ever since been most zealous in using it to the best advan- 

 tage." 



It is not expected that the new views of physics will be ge- 

 nerally accepted without vigorous opposition. A large amount of 

 intellectual capital has been honestly invested in the fortunes of 

 the other side. The change is recommended by powerful phy- 

 sical arguments, and it disenthralls the theories of science from 

 many metaphysical difficulties which weigh heavily on some 

 minds. On the other hand, the style of mathematics which the 

 innovation introduces is novel and complex; and good mathe- 

 maticians may find it necessary to goto school again before they 

 can read and understand the strange analysis. It is feared that 

 with many, who are not easily deflected from the old ruts, the 

 intricacies of the new mathematics will outweigh the superiority 

 of the new physics. 



The old question, in regard to the nature of gravitation, was 

 never settled ; it was simply dropped. Now it is revived with as 

 much earnestness as ever, and with more intelligence. Astro- 

 nomy cast in its own mould the original theories of electrical 

 and magnetic action. The revolution in electricity and mag- 

 netism must necessarily react upon astronomy. It was proved 

 by Laplace, from data which would now probably require a 

 numerical correction, that the velocity of the force of gravitation 

 could not be less than eight million times the velocity of light ; 

 in fact, that it was infinite. Those who believe in action at a 

 distance cannot properly speak of the transmission of gravitation. 

 Force can be transmitted only by matter, either with it or through 

 it. According to their view, action at a distance is the force, 

 and it admits of no other illustration, explanation, or analysis. 

 It is not surprising that Faraday and others, who had lost their 

 faith in action at short distances, should have been completely 

 staggered by the ordinary interpretation of the law of gravitation, 

 and that they declared the clause which asserted that the force 

 diminished with the square of the distance to be a violation of 

 the principle of the conservation of energy. 



Must we, then, content ourselves with the naked facts of gravi- 

 tation, as Comte did ? or is it possible to resolve them into a 

 mode of action in harmony with our general experience, and 

 which does not shock our conceptions of matter and force ? In 

 1798, Count Rumford wrote thus: — "Nobody surely, in his sober 

 senses, has ever pretended to understand the mechanism of gra- 

 vitation." Probably Rumford had never seen the paper of Le 

 Sage, published by the Berlin Academy in 1782, in which he 

 expounded his mechanical theory of gravitation, to which he had 

 devoted sixty-three years of his life. In a posthumous work, 

 printed in 1818, Le Sage has developed his views more fully. 



