Please see Transcriber’s Notes at the end of this document.
HOW COLOR PRINTING IS DONE
A plate is made for each of the three printing colors, yellow, red and blue, as explained on page 382.First, yellow is printed, then red on the yellow, and last, blue on the yellow and red combination. Combinationsof these three colors in various proportions produce all the other tints which appear in the originalsubject. Above are shown the separate plates and also the combined result of all three. Extreme care isnecessary to make all the plates register exactly together.
THE WONDER BOOK
OF KNOWLEDGE
THE MARVELS OF MODERN INDUSTRY AND INVENTION
THE INTERESTING STORIES OF COMMON THINGS
THE MYSTERIOUS PROCESSES OF NATURE
SIMPLY EXPLAINED
COMPILED AND EDITED
BY
HENRY CHASE HILL
WITH THE CO-OPERATION OF EXPERTS
REPRESENTING EACH INDUSTRY
Illustrated with
780 Photographs and Drawings
PHILADELPHIA
THE JOHN C. WINSTON COMPANY
PUBLISHERS
Copyright, 1921
By L. T. MYERS
Copyright, 1917-19
Preface
This book is presented to those, both young and old, who wish to have a non-technicalaccount of the history, evolution and production of some of the every-daywonders of the modern industrial age; coupled with occasional glimpses of the wonderfulobject-lessons afforded by nature in her constructive activities in the animal,vegetable and mineral kingdoms; and simple, understandable answers to the myriadpuzzling questions arising daily in the minds of those for whom the fascination ofthe “Why” and “How” is always engrossing.
Although not intended primarily as a child’s book, the interest-compelling picturesand clear, illuminating answers to the constant avalanche of questions suggestedby the growing mind, unite in making far happier children in the home andbrighter children at school. Parents and teachers will also recognize the opportunityto watch for subjects by which the child’s interest appears to be more than ordinarilyattracted, and, in so doing, will be enabled to guide the newly-formed tendencies intothe proper channels. With the greatest thinkers of the age advocating vocationaltraining, and leading educators everywhere pointing out that the foundation of apractical education for life must be laid in the home, thoughtful parents will notoverlook the fact that a book which both entertains and instructs is of supremeimportance in the equipment of their children.
In the preparation of this book its function has been considered as that of gatheringup some of the multitudinous bits of information of interest, both to the inquiringchild and the older reader, and putting them in shape to be digested by the ordinarysearcher after knowledge. The book is intended, not for a few technical specialists,but for the larger