Industrial economy demanded the expert with his high and special standards of achievement.

The railroads and factories could not be financed and operated without the assistance of well-paid and well-trained men, who could do one or two things remarkably well, and who did not pretend to do much of anything else.

These men had to retain great flexibility and an easy adaptability of intelligence, because American industry and commerce remained very quick in its movements.

The machinery which they handled was less permanent, and was intended to be less permanent than the machinery which was considered economical in Europe.

But although they had to avoid routine and business rigidity on the penalty of utter failure, still they belonged essentially to a class of experts.