sundial (sundi"al)

[Early mod. E. also sunne - diall; ۱۸ Sun-dial. Face of horizontal dial, shadow pointing to one o'clock. ples of 15°) be cut by the plane of the dial, the intersecting lines will be in the positions of the hour-lines of the dial. The shadow of any given point upon the gnomon edge will fall at different positions on the hour-line according to the declination of the sun, and this circumstance may be used to make the dial show mean instead of apparent time. But this is inconvenient, and seldom used. Portable sun-dials used often to be made so that their indications depended exclusively on the altitude of the sun; such dials require adjustment for the time of the year. See dial. To rectify a sun-dial. See rectify.