THE SUBJECT CONTINUED. 229 



as a mechanical power that could be carried about, 

 and applied where and when you pleased, except 

 animal power. The plow, the spade, or the hoe, 

 (with their varieties,) were the only possible modes 

 of effecting the task of cultivation. The compara- 

 tively recent discovery of steam-power altered the 

 condition of human life in this particular. The 

 modes of action to which cultivation was before 

 limited, and which are exemplified in the use of 

 the three instruments just named, became, on the 

 discovery of steam, no longer the necessary and only 

 modes of performing the act of tillage. From the 

 nature of things it was morally certain that when- 

 ever that new Power was applied to this act, it 

 would be through an instrumentality as different 

 from the plow as the plow was from the spade. If 

 a man will only give himself the trouble to think 

 how total a revolution the application of steam 

 effected to the navigation of a ship, and the locomo- 

 tion of a carriage, he cannot very well fail to see 

 what is meant by the saying, that a new power 

 requires a new process. It is a solecism in art, as 

 well as science, to attempt to yoke steam on to the 

 plow. There is no affinity between them; any 

 more than, as I said before, between a horse and a 

 spade. 



