PREFACE
This book was written primarily for the student Gunner's Mate, and was designed for use in Naval Gunner's Mate Schools which provide a course in basic hydraulics.
Normally the basic hydraulics course is covered in a relatively short period, and is followed by other courses leading to a more specialized study of ordnance hydraulic systems. It is highly important that the Gunner's Mate have a sound knowledge and understanding of basic hydraulic principles before he starts his specialized studies. Because the students who take the basic course vary in their experience with hydraulic systems, there is every reason for simplicity and clarity in this presentation.
It was realized that knowing how a system works is just as important as practical acquaintance with the system. Neither form of experience is a substitute for the other. An effort has therefore been made not only to describe but to explain.
It is nevertheless a fact that much remains unexplained in this book, and must be accepted as part of the body of scientific thinking. There are no mathematical demonstrations, and very few formulas. Wherever possible the principles of hydraulics have been shown to, be consistent with everyday knowledge and experience.
It is believed that this volume will be of value to all branches of the service which employ hydraulic equipment. Acknowledgement is made of the cooperation of the Bureau of Ships and the Bureau of Ordnance in the preparation of this manual.