## Principle and Use of Ottoman Sundials

Muslim astronomers and engineers invented a variety of dials for timekeeping and for determining the times of the five daily prayers. In this thorough and technical study, Professor Attila Bir analyses the principle and use of Ottoman sundials. Beginning with the definition of the the day, the hour and the prayer times, he analyses the mathematical formulas of the main two varieties of suncials used by Ottoman astronomers, the horizontal and vertical sundials.

Rate this article: