112 LIFE IN NATURE. 



must be the result of motion in the direction of least 

 resistance. I am aware, however, that this may 

 seem to be, though a true, yet a one-sided statement. 

 For though motion cannot but take the direction 

 of least resistance, yet it is determined, not only 

 by the resistances it meets, but even more directly 

 and decisively by the original impulse which occasions 

 it. Every motion has, at any given moment, an 

 existing course, or arises from a force operating 

 in a given direction ; and the impulse of this force 

 may be sufficient to carry it through, and cause 

 it to overcome, great resistance, even though in 

 other directions there may be less or none. The 

 very use of a bullet or cannon-ball, for example, 

 is to overcome resistance. But the deficiency in 

 the form of the axiom when thus regarded is but 

 apparent, and arises from our confining our view 

 within too narrow a sphere : when we take all the 

 conditions into consideration, it appears to be suffi- 

 ciently ample and exact. 



It is true there is a certain direction possessed 

 by every existing motion, or given to every motion 

 at its origin; but we must remember that we may 



