THE LAWS OF LIFE. 253 



oxygen with zinc, or that the ascent of one weight 

 bears to the descent of another. Living germs 

 permit decay by taking up absorbing, it might 

 almost be said the resulting force. They act the 

 part of a good conductor around the heated wire. I 

 may observe here an instance of beneficent adapta- 

 tion. Uecay being to so great an extent dependent 

 upon the occurrence of vital action, the source of 

 life is husbanded and reserved for the purposes of 

 life. If complete decomposition took place rapidly 

 in the soil independently of the existence of vegeta- 

 tion, how sad a barrenness would overspread the earth. 

 But God has ordained it otherwise, and the life-pro- 

 ducing chemistry tarries at his bidding for the germ. 

 Motion takes the direction of least resistance. If 

 the resistance be absolute this direction is at right 

 angles to the line of the original motion. That this 

 must be the case is obvious, the rectangular direction 

 being the mean between the momentum of the 

 motion and the resistance supposed. And it is so in 

 fact. A current of air striking against a flat surface 

 passes off at a right angle in all directions: a soft 

 mass propelled against such a surface becomes 



