"Young Engineer's Guide" by J. V. Rohan is a practical guidebook on operating and maintaining steam engines and boilers written in the late 19th century. The book is aimed particularly at young engineers and those new to operating farm engines, providing relevant mechanical information to help them understand the care and operation of steam-powered machinery. The opening of the guide outlines the author's motivation for its writing, explaining how he recognized a need among young, mechanically inclined men seeking systematic information about steam engines. Rohan states that he aims to condense practical knowledge into a conversational format, presenting technical concepts in simple terms that are designed to empower novice engineers. The initial sections cover hints for purchasing engines, the vital duties of engineers, and an introduction to various types of boilers, laying a foundation for the more detailed technical instructions found later in the guide. (This is an automatically generated summary.)