Continental drift my lecturers why he was not talking to us about continental drift and I was told, sneeringly, that if I could prove there was a force that could move continents, then he might think about it. The idea was moonshine, I was informed." As late as 1953 – just five years before Carey introduced the theory of plate tectonics – the theory of continental drift was rejected by the physicist Scheidegger on the following grounds. From the 1930s to the late 1950s, works by Vening-Meinesz, Holmes, Umbgrove, and numerous others outlined concepts that were close or nearly identical to modern
Drift pin is driven in, the taper forces the two components into alignment, allowing for easy insertion of the fastener. Unlike most punches, force should never be applied to the tip of drift pin. Drift pins are especially useful for aligning fastener holes in structural steel members. Spud wrenches used for assembling trusses and steel beams have tapered handles to use as drift pins. Drift pin In metalworking, a drift pin, drift pin punch, slave pin, simply drift, or even pokey bit is the name for a tool used for enlarging holes, or aligning holes prior to bolting or riveting metal parts