Transcriber’s Notes

Punctuation, hyphenation, and spelling were made consistent when a

predominant preference was found in the original book; otherwise they

were not changed.

Simple typographical errors were corrected; unbalanced quotation

marks were remedied when the change was obvious, and otherwise left

unbalanced.

Illustrations in this eBook are shown as close as possible to their

original positions in the printed book, so several of them actually are

mid-paragraph. This was done because some of them are referenced only

by their content, not by their names.

This book does not have a Table of Contents.

The index was not in good alphabetical order; Transcriber re-sorted it.

It was not checked for correct page references.

A boy's text book on gas engines · 第 20 / 20 题