Publications

The Glossary

This is a 90 page document which lists most all of the terms which are directly related to dials and dialling. Additionally, excursions into the fields of astronomy, horology, optics and solar sciences have been made where it seems useful. There are a set of thumbnail biographies of the major players in the development of dialling, detailed equations for many dial types, and a set appendices providing comments on the history of dialling and various solar and other data.

Edited by John Davis

The Double Horizontal Dial

BSS Monograph No. 5

The double horizontal dial combines two forms of sundial, a common horizontal dial and one having a vertical gnomon which indicates the position of the sun on a stereographic projection of the celestial sphere. This is an exhaustive and meticulously researched treatise on the subject which is the definitive reference on double horizontal dials, their history and their makers.

By John Davis and Micheal Lowne, 240 pages

Altitude Dials

BSS Monograph No. 4

The history of portable sundials starts probably around 1500 BC in Egypt with the construction of an altitude dial.

For the following centuries, measuring the height of the Sun in the sky remained the favourite method for determining time in the field of portable sundials. Here 38 types of altitude dial are listed and described. For each of them a model was made and documented with a photograph. Fundamental considerations on the accuracy of each type and helpful advice on usage from the examination of each model are added.

Mike Cowham, 63 pages