Bharatiya Jyotihshastra (History of Indian Astronomy), translated by R. V. Vaidya v2.c12.s5.25

v2.c12.s5.25

4. *The Gola instrument* (Globe instrument) :—Placing a ‘bhagola’ in a ‘khagola’, mark a spot on the ecliptic ring at a place where the sun is expected to be on a particular day. Then so rotate the ‘bhagola’ that the mark will cut the horizontal circle. Mark that point in the horizon in which the plane of the equator in the ‘bhagola’ will appear to cut. Then again rotate the ‘bhagola’ so that the spot marking the Sun’s position will cast a shadow on the ‘bhugola’ i.e., the terrestrial globe. Where the shadow is cast, the number of ghaṭis indicated between the spot and the ‘nāḍivalaya’ will give the number of ghaṭis elapsed after sunrise on that day. Then the point of the ecliptic in contact with the horizon will give the ascendant at the moment.