The Indus Civilization (Cambridge History of India, Supplementary Volume) c15.22

c15.22

Measurements of length appear to have followed a decimal system, if a graduated fragment of shell from Mohenjo-daro is rightly interpreted as a part of a scale.⁴ It is divided accurately into units of 0.264 in. with a mean error of only 0.003 in.; and, of the nine divisions preserved, a group of five is demarcated by dots, of which one (perhaps marking the tenth of a series) is further emphasized by a circle. The five divisions represent 1.32 ins., which may have risen to a "foot" of 13.² ins. This would equate with a widespread northern or north-western foot traceable to XIIth Dynasty Egypt on the one hand and to British medieval building on the other.