Classicly

Diggers in the Earth is a book on mining engineering wrtiten  by Eva March Tappan, a teacher and American author whose other books including England's Story,American Hero Stories, Old World Hero Stories,Story of the Greek People, Story of the Roman People, etc. Editor of The Children's Hour.

Author's Preface:

The four books of this series have been written not merely to provide agreeable reading matter for children, but to give them information. When a child can look at a steel pen not simply as an article furnished by the city for his use, but rather as the result of many interesting processes, he has made a distinct growth in intelligence. When he has begun to apprehend the fruitfulness of the earth, both above ground and below, and the best way in which its products may be utilized and carried to the places where they are needed, he has not only acquired a knowledge of many kinds of industrial life which may help him to choose his life-work wisely from among them; but he has learned the dependence of one person upon other persons, of one part of the world upon other parts, and the necessity of peaceful intercourse. Best of all, he has learned to see.