English: Dialing scales are used to construct sundials. They were first described by Samuel Foster in 1638. Drawn by Serle, Middleton 1913 and Anthony for NASS.
A right-angle is drawn on the dial-face and the latitude scale is laid against the x-axis. The target latitude point is marked across on to the dial face.
The hour scale is placed from this point to the noon line, conventionally the zero point is on the noonline.
Each of the hour points are copied over to the dial face, and this procedure is repeated giving the hours both sides of noon. A straight edge is used to connect these points to the origin thus drawing the hour lines for that location.
A vertical line from the target latitude point, and a horizontal line through the noon point will bissect at the three hour (9am - 3pm) marker.
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