The Daily Phoenix

The Age of the Earth.--The new method of ascertaining the age of the earth, which is a present topic in German scientific circles, attempts to determine approximately the time at which the fiery liquid earth ball for the first time covered itself with a solid crust. This is done by means of the difference of the longest and shortest diameter of the earth. According to the calculations of Newton and Huygens, this would be 1/315 if the rotation of the earth had always been completed in twenty-four hours, while in fact it amounts to 1/289, which is equivalent to a rotation time of seventeen hours and sixteen minutes, which must once have been the earth's time of rotation. It is, however, probable, for reasons which need not be gone into here, that at the time the earth was covering itself with a firm crust, the time of rotation was already a mean between the original and the present time. That a retardation of the rotation time has taken place and is still taking place is now as good as proved, although formerly it was strongly doubted.

Of all heavenly bodies it is the moon whom astronomers know best, and have most exactly calculated from her movements. Now, the coefficients of the secular acceleration of the moon's course, as found on the one hand from the oldest observations of eclipses, on the other from theory, are at variance, and there are differences which ought not to exist in the calculations of so well-observed a body. Agreement can only be obtained when it is supposed that during the 2,000 years which have passed since the Greeks first calculated the eclipses, the rotation of the earth has been retarded 0.0197 seconds. There exists no difficulty about the causes of this retardation, which is perfectly well explained by the tides. From the cipher thus found it is easily calculated how much time will be required to cause a retardation of nearly four hours, and the result is that since the first crust of the earth formed itself more than 2,000,000,000 of years must have elapsed.