Science: Our Unstable Globe

The gist of a dissertation* recently prepared for Nature (London) by Professor W. de Sitter of the University of Leyden, Netherlands:

It has long been suspected that the rotation of the earth is gradually slowing down. But lately other doubts have arisen. As a matter of fact, it is not the rotation of the earth, but of a definite point on the earth—the Greenwich or some other observatory—that is used as our standard. Comparison of wireless time signals has revealed slight discrepancies from different observatories. While these may be due to errors in instruments,...