""A Manual of Quaternions"" is a comprehensive guide to the mathematical system of quaternions, written by Charles Jasper Joly. Quaternions are a type of hypercomplex number system that extends the properties of complex numbers to three dimensions. This book provides a thorough explanation of the principles of quaternions, including their algebraic properties, geometric interpretation, and applications in physics and engineering. The author also includes numerous examples and exercises to help readers understand and apply the concepts presented in the book. This text is suitable for advanced undergraduate and graduate students in mathematics, physics, and engineering, as well as researchers and practitioners in these fields.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.