Observational Geometry is a comprehensive textbook written by William Taylor Campbell and first published in 1899. The book is a detailed guide to the principles and methods of observational geometry, which is the study of the relationships between points, lines, and planes in space. Campbell's book covers a wide range of topics related to observational geometry, including the use of instruments such as the theodolite and the transit, the measurement of angles and distances, and the calculation of areas and volumes. The book also includes detailed discussions of trigonometry, spherical geometry, and the use of logarithms in calculations.The text is written in a clear and concise style, with numerous diagrams and examples to help readers understand the concepts and methods presented. The book is intended for students of surveying, engineering, and other fields that require a strong understanding of observational geometry.Overall, Observational Geometry is a valuable resource for anyone interested in the principles and methods of observational geometry, and remains an important reference work in the field.This scarce antiquarian book is a facsimile reprint of the old original and may contain some imperfections such as library marks and notations. Because we believe this work is culturally important, we have made it available as part of our commitment for protecting, preserving, and promoting the world's literature in affordable, high quality, modern editions, that are true to their original work.