Islamic horary quadrant

Image number: 1918-0261_0002_0003

Islamic horary quadrant

Horary quadrants determine the time from the altitude of the Sun. This Islamic instrument may have been used to calculate prayer times.

Highly portable, it can be used from any location on Earth. The lines on the front represent the motion of the Sun across the sky.

Image number:
1918-0261_0002_0003
Credit:
Science Museum/Science & Society Picture Library
Image rights: