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. Combinations of these three colors in various proportions produce all the other tints which appear in the original subject. Above are shown the separate plates and also the combined result of all three. Extreme care is necessary 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

THE WONDER BOOKOF KNOWLEDGE

THE WONDER BOOK
OF KNOWLEDGE