1. Home
  2. /
  3. Bulletin Archive
  4. /
  5. Tony Belk

Tony Belk


An extension of a previous article on a photographer's sundial. This part adds a scale to indicate the sun's altitude and provides a new design for use at 54° N, which, together with the original 51.5° N dial, covers all of England.
DIY Sundial Projects, How Sundials Work, Sundial Design & Layout

This report covers the fourth BSS Sundial Design Competition, which received 14 entries across restoration, professional, and amateur classes, though no junior entries. Graham Aldred won the Major Prize for his restoration of the Lyme Park dial. Other prizes were awarded for a south-facing vertical dial and highly commended entries for a sun/moon dial, a prototype noon mark dial, and a vertical dial using a 'super ellipse.'
Dials: Unusual, Restoration projects, Sundial Design & Layout, The BSS and Members

An analysis of the time-telling errors that occur when a horizontal or vertical non-declining sundial is used at a latitude different from its design latitude. The article provides tables and graphs illustrating the magnitude of these errors at different times of day and for different solar declinations.
Dials: Horizontal, Dials: Vertical, How Sundials Work, Mathematics of Dialling

Describes the design and use of a pocket-sized device for photographers to predict the sun's direction at any time of day or year. Based on a horizontal stereographic projection, the instrument uses a rotating dowel aligned with date and time scales to help plan for specific lighting conditions.
DIY Sundial Projects, Dials: Unusual, Sundial Design & Layout

A light-hearted alphabetical list of terms and concepts related to sundials and dialling. It covers various aspects from Apparent time to Zodiac, including types of dials, mathematical concepts, and references to the British Sundial Society and its members.
How Sundials Work, The BSS and Members

This article presents a method for designing polar sundials for any latitude and declination using four simple formulae. It explains that polar dials have a style parallel with the dial plane and parallel hour lines, and describes how to determine the angle of the equinox line and the sub-style hour angle.
Dials: Polar, How Sundials Work, Mathematics of Dialling, Sundial Design & Layout

This article offers detailed methods for drawing declination lines on planar sundials using polar and Cartesian coordinates, or a graphical protractor, all based on the dial's style height and nodus distance. It also provides formulas for calculating hour line angles for various dial types and a simple method to check existing dials for accuracy.
Construction Projects, Dialling Tools, Mathematics of Dialling, Sundial Design & Layout

This article introduces a user-friendly method for delineating vertical declining sundials using bespoke slide rule-like calculators. These tools determine equivalent latitude and longitude, simplifying the process by eliminating complex trigonometry. The article explains how to use these calculators with standard dialling scales to accurately plot hour and sub-style lines.
Dialling Tools, Dials: Vertical, Mathematics of Dialling, Sundial Design & Layout

Explains how direction cosines can be used to precisely design planar sundials. The method eliminates inaccuracies of graphical construction by calculating hour lines, declination lines, and style parameters mathematically, with examples for horizontal, vertical, and declining dials, and comparison with conventional calculation methods.
Mathematics of Dialling, Sundial Design & Layout

A summary of the British Sundial Society's Annual Conference at Yarnfield. The report covers various talks and workshops, including one on electrochemical hazards to sundials, a presentation on a pilgrim route, and one on unusual sundial designs.
The BSS and Members

A detailed explanation of a unique 1803 sundial with a moon time calculator by Isaac Morris, exploring its design, mathematics, and possible use for tide prediction.
Historical Dials, Dials: Nocturnals

This second part details using stereographic projection for graphical design of declining and reclining vertical, and double horizontal sundials. It explains how to determine sub-style angles and style heights, and how the projection can cover full 24-hour periods. The article also covers William Oughtred"s "Horizontal Instrument" and Blagrave"s "Mathematical Jewel" as related applications.
Dials: Double Horizontal, Dials: Vertical, Mathematics of Dialling, Sundial Design & Layout