Number 60 in Time Measurements

Abstract

WITH reference to the note in NATURE of March 4, p. 299, may I point out that the cycle of 60 years does not appear to date back before the Han dynasty (say 200 B.C.), and that the cycle of 60 before that date only occurs in the actual records as applied to days, probably back to about 2000 B.C. There are traces of a 10-day period in the ritual records and this may predate the 60-day period. T. Fergusson considered the 60-years period to have been borrowed from India and to be the cycle of conjunctions of Jupiter and Saturn in the same geocentric longitude, but beyond the fact that Szuma ch'ien used some queer foreign names for the years of the 60 cycle, there is no real evidence.