Picture shows the "Table of reciprocals of 60" (2100 BC to 2000 BC) from southern Iraq. The central numerical system which underpinned 3,000 years of daily Mesopotamian calculation was the sexagesimal system - counting in 60s, our division of hours and minutes into 60 units is a direct descendent of Babylonian systems of counting and measurement. This exhibit is on display at the Hong Kong Museum of History's "The Wonders of Ancient Mesopotamia" exhibition.   Close