This fascinating book provides a detailed introduction to the sector and plain-scale, important tools for navigation and surveying. It covers the basic principles and techniques of using these tools, with clear and concise explanations and practical examples. The book also includes a brief history of these instruments, and explores their uses in a range of fields, from astronomy to engineering. Whether you're a history buff, a mathematician, or just curious about the world around you, this book is a must-read. This work has been selected by scholars as being culturally important, and is part of the knowledge base of civilization as we know it. This work is in the "public domain in the United States of America, and possibly other nations. Within the United States, you may freely copy and distribute this work, as no entity (individual or corporate) has a copyright on the body of the work. Scholars believe, and we concur, that this work is important enough to be preserved, reproduced, and made generally available to the public. We appreciate your support of the preservation process, and thank you for being an important part of keeping this knowledge alive and relevant.