Remarks on Inertia. 57 



Why action and reaction are equal, we pretend not to give 

 any reason except that such is the constitution of matter. . 



We have a striking example of the errors which arise from 

 losing sight of the technical meaning of terms, and taking 

 them in their literal signification, in the July number of the 

 Franklin Journal : the new theory of falling bodies is in our 

 opinion based upon the deception, which has originated in 

 the phrase, "force of inertia," although this phrase is avoided 

 in the essay. This is the age of discovery, and it appears 

 that our western regions are not to be deficient in bringing 

 forth things vast and wonderful, however we may fail in re- 

 ducing them to shape and symmetry : but we are not all 

 Symmesonians, neither do we all believe in the " Bakewellian 

 Lecture,' 1 which Prof. Jones has thought worthy of a place 

 in his Journal. Perhaps as this discovery came from the 

 west, it will not be thought presumptuous in a western man 

 to make a few remarks on it, especially as the theory proves, 

 that in our observations on inertia, we have not been combat- 

 ting with creatures of the imagination only. 



Mr. Bakewell may mean one of two things in his first and 

 principal proposition : (since the second is only a corollary 

 from it,) either that the attraction of gravitation is a constant 

 force at all distances ; — always the same, and consequently 

 always producing equal velocities : or that gravitating forces, 

 however different in intensity will cause equal velocities. 

 The first position is contradicted both by reason and experi- 

 ment ; and the second is in itself absurd : since it makes un- 

 equal causes produce the same effects. Force is explained, 

 as well as that which expresses something in itself simple and 

 indivisible can be, from its effect ; force then is that which 

 causes motion. That unequal forces therefore, or unequal 

 causes of motion should produce equal velocities, is not very 

 evident, to say the best of it : we mean that the truth of the 

 proposition is not very evident ; for as to the proposition it- 

 self, a man of the plainest judgment could decide upon it 

 without a moments hesitation, but the theory is unworthy of 

 a detailed consideration ; we will endeavor " to trace the 

 error to its, fountain head and thus refute it." 



"The fall of bodies," says Mr. B., "would be instantane- 

 ous from any distance however great, but for the inertia of 

 matter." What can be the meaning of the term inertia, in 

 this sentence ? how can the passiveness of matter have any 

 influence in diminishing the velocity caused by the force of 



Vol. XIV.— No. 1. 8 



