The boy was becoming the teacher, and the father was taught.

By the time Cyrus was eighteen, indeed, he had advanced so far beyond his father that the latter had become merely a proud observer.

Young McCormick threw into the discard all his father's ideas and struck out on entirely new lines.

By the time he had reached his twenty-second birthday he had constructed a machine which, in all its essential details, is the one which we have today.

He had introduced seven principles, all of which are an indispensable part of every reaper constructed now.