The International Exhibition: Bramahs lock and key, 1862. Diagrams of ...the Bramah lock - the first showing a view of the lock generally known as a latch. The mechanism is exceedingly simple, and consists mainly of a spring contained within the brass cap. The second Engraving represents the key and a sectional view of a larger lock containing the spring and slides. The Bramah principle is now well known, and consists of notches in the pipe of the key, which fit corresponding guards in the interior of the lock. By this means a very small key is obtained, such as can he used as a chain or any other ornament. A key that will unfasten the lock of a large safe can even be fitted to a ring. From "Illustrated London News", 1862.