(Jon of the Clue Crew points to an astronomical diagram on the monitor.)  In the 200s B.C. Eratosthenes calculated Earth's girth using the difference in the angle of the Sun's rays between Aswan & this Egyptian city
India, the zero was used by the math- ematicians... [DOC] [TLE] the 69198101 of 39753271 and 28546808 in 27762992 - Sphinx [PAR] ... category 7425339 http 7232611 by 7219185 with 6772307 www 5598069 from 
... 1646873 10 1629611 left 1622200 city 1595611 no 1577260 other 1566008 c 
... about 988764