'The Principles of Masonic Law' is a treatise on the constitutional laws, usages and landmarks of Freemasonry, divided into four books. In it, author Albert Gallatin Mackey presents the principles of Masonic law in an elementary and methodical way that enables every Mason to know their rights and learn their duties. Mackey explores the unwritten and written laws of Masonry, including ancient usage and regulations adopted at various annual communications. This book provides insight into the organization and powers of grand lodges and subordinate lodges, the rights of individuals at different levels of the Masonic hierarchy, and punishments for Masonic crimes.