282 KINETIC THEORIES OF GRAVITATION. 



sach a theory or hypothesis of attraction, the obvious answer is, there 

 is neither "theory" nor "• hypothesis" in the case. The observed fact 

 that one body does actually induce approach in another body at a dis- 

 tance from it, if accepted as an "ultimate" one, is of course thereby ex- 

 cluded from all idea of "explanation." And as this observed fact, by 

 the multiplicity of instances in which no intermediate agent has yet 

 been detected, or rendered rationally plausible, is generalized into an 

 " induction," the burden of proof lies entirely "on tbe shoulders of those 

 who with a keener vision through nature's veil, are ready to proffer 

 hypotheses "without assumptions," and endless motions without the 

 aid of " occult qualities." 



But this stern requirement of a demonstrated instance of material 

 link, or mechanical connection, to impugn the large induction of an 

 actio in distans, cannot be evaded by the logical artifice of designating 

 such "induction" as a competing "hypothesis!" If by the scientific 

 method of a carefully registered experience such theorists should ever 

 be successful in pJiysically justifying their ill-advised scruples, their 

 mala fastidia, (to use the phrase of Horace,) none will be more heartily 

 rejoiced at this new conquest over ignorance than the astronomers and 

 physicists who hitherto have given themselves but small concern re- 

 specting the metaphysical paradoxes supposed to be involved in the 

 more usual statement of the law of gravitative action. 



But as yet this generalization, after two centuries of busy thought 

 and daring speculation, still remains the largest, clearest, surest, yet 

 attained by man ; and with each revolving year new demonstrations of 

 -its absolute precision and of its universal domination serve only to fill 

 the mind with added wonder and with added confidence in the stability 

 and the supremacy of the power in which has been found no variable- 

 ness, neither shadow of turning, but which, the same yesterday, to-day, 



and forever, 



" Lives through all life, extends through all extent, 

 Spreads undivided, operates — unspent!" 



