***Completely revised version of the original 1922 edition*** "The Chaldeans used to predict the eclipses three thousand years ago; with a degree of accuracy that is only surpassed by seconds in these days because we have wonderful clocks which they had not. Yet they had an entirely different theory of the universe than we have. The fact is that eclipses occur with a certain exact regularity just as Christmas and birthdays do, every so many years, days and minutes, so that anyone who has the records of the eclipses of thousands of years can predict them as well as the best astronomers, without any knowledge of their cause."