"The line which passes through Lanka, Vatsyapura, Avanti, Sthánesvara, and the "abode of the gods" [= Mount Meru = north pole] is the prime meridian [desantara vidhàyani, lit. the prime meridian for longitude differences.]"
January 1, 1970
https://en.wikiquote.org/wiki/Bh%C4%81skara_I