SUNDIAL SECTIONS:

Sundials Home

History of Sundials

Why the Sun Dial keeps time

Developing and Making Sundials

Sundial Materials

Sundial Hour Lines Lay out

Sundial "Furniture"

Declination Lines of Sundials

Portable Sundials

Interesting Sundials of the World

LAYING OUT THE SUNDIAL HOUR LINES - Page 17

Two reclining sundials have been described in the foregoing pages: the equatorial, a north recliner; and the polar, a south recliner. These two sundials take their names from the planes in which they lie. For this reason they are not usually classed with the reclining sundials. The direct reclining sundials are so-called because their planes face the cardinal points of the compass, and as you stand before them they lean from you (or recline from the zenith). A plumb line is perpendicular to the plane of the horizon and if extended, it would cut the zenith at any given place. The reclination of a sundial or plane is that angle, measured in degrees, formed by the intersection of the sundial or plane with a plumb line. Before the hour lines can be computed the sundials must be referred to that position in which they would become horizontal or vertical sundials. This is called "reducing to a new latitude". The method of reduction is but a simple arithmetical operation.

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