The 34-degree secret: How ancient magnetism exposed a planet in motion

The 34-degree secret: How ancient magnetism exposed a planet in motion

At 9:42 a.m. on a cool March morning in 1954, inside a basement laboratory at Cambridge University, a narrow needle in a magnetometer twitched just slightly off its mark. The instrument was old even then, a balanced coil designed to measure the fossilized magnetism trapped inside stone. J. A. Clegg leaned closer, watching the trace drift thirty-four degrees clockwise from true north. The rock sample was Triassic sediment taken from a quarry in W…