This work examines the portable sundials which were the everyday timekeepers used by both rich and poor for three millennia, before they were superseded by the watch. It aims to demonstrate the vital role which sundials played in the world for many centuries. The book is laid out chronologically, with individual chapters covering particular periods of history. While the focus is on the sundials themselves, much reference is made to the contemporary social, political and economic history, so that the subject matter is firmly set in context. Each chapter picks one or two detailed examples as a focus for the wider field. Most of the sundials come from the collections of the National Maritime Museum, but where gaps need to be filled, dials from other collections have been chosen. Dials from all the manufacturing countries throughout the world are included. The illustrations form an essential part of the book, both as an aid to explaining how the dials work, and because many are functional works of art of high visual quality. The detailed examples in each chapter are fully illustrated.
Diagrams have also been provided to explain in easy terms some of the complicated mathematics involved in the construction and use of dials. Other illustrations have been selected to complement the background of historical material.