The angle between the cone s axis and the horizon equals the latitude, but this cannot be measured directly. We only have the angles between the actual surfaces, the distance to the arcs, and the arc lengths to work with. 3, the author prefers angle alpha, this being a direct function of the latitude. The arc lengths are not dependable upon, because the latitude is a very sensitive function of it. The actual Leyden dial is now discussed.
Measurements are in fig.
Angle alpha gives a latitude of 37, slightly south of Athens where the dial was found. The date arcs are perfectly circular and perpendicular to the cone s axis. A table lists actual and calculated measurements. The author concludes that the stonemason was a sundial professional. An invitation to discuss the relative merits of both hour line systems.