Octagonal plate, 520mm across flats, 28mm thick
Gnomon, water-jet cut brass and slate 12mm thick, 400mm long.
Cursor: water-jet cut and stove enamelled etching, on stainless steel pin.
Materials: Plate: Welsh blue-black slate, brass, stainless steel
Location : In private ownership, Lat. approx. 51⁰N
Designed, delineated and hand cut by David Brown
This sundial is known as M29 in ‘The Double Horizontal Dial’ BSS Monograph 5 (2009) by J. Davis and M. Lowne. It is described therein, but without an adjacent photograph because it had been planned but not yet made in time for publication. The completed sundial carries the date MMX when work on it began, but it was not finished until 2013.
It is thought to be the only slate double horizontal sundial in existence whose whereabouts are known.
Much help in the design process was obtained from ‘The Astrolabe’ by James E. Morrison ISBN 978-0-939320-30-1 as well as the BSS Monograph above and help with calculations from John Davis.