The fact that the grains of ancient rocks are lined up like tiny compass needles has led to the astonishing conclusion that the earth's magnetic poles have wandered and reversed By S. K. Runcorn ...

WHEN the mean horizontal force of the earth's magnetism for each day of the year has been deduced from well-corrected observations of the bifilar magnetometer, and the results have been projected ...

Electricity and magnetism were imprinted into our surroundings from the beginning. Five billion years ago when the new-born Earth was a hot plasma of swirling electrical currents, these flows ...