Clearview (59 High Street, Eydon) is possibly the the site of the oldest east-facing house sundial in Britain dating from possibly the 15th century.
In total it has three dials, with this mass dial scratched into the lintel of the round-topped door furthest from the street. The terms 'scratch dial' and 'mass dial' are used to describe rough circles or semi-circles which are scratched (rather than cut) on the stone walls (usually) of churches.
Basically they are a very early type of sundial which is a means of telling the time by marking the movement of the shadows made by the sun. Most of them are marked with uneven hours. Over the centuries, many various and ingenious methods of producing the shadow and marking the time have been developed.
In Eydon most of the dials are vertical wall ones in which a pointer (the gnomon) casts a shadow onto markings carved onto the wall. They have various numbers of lines radiating from a central hole which once contained either a metal or wooden pin projecting to cast a shadow (this is called a 'style' or 'gnomon').
The lines were thought to indicate to the priests the hours when services were to start according to Canon Law. It is thought that the Arab philosophers developed the theory of 'equal time' in which the hours were of fixed duration. This led to the 'scientific' sundial, in which the gnomon is parallel to the rotational axis of the earth (less complex that it sounds - you just need to point it at the Pole Star). It enabled hours of equal length to be measured. Despite this being developed by the 13th century, it took until the late 16th century for these dials to become known in Britain. Photographer: Dr Kevin Lodge
Image lent by : Dr Kevin Lodge
Connected Photos: AP056 | AP057 | AP058 | AP059 | AP060 | AP061 | AP062