The Q.H.M. magnetometer:



Pointy magnetometer

Developed for use in finding submarines under water, the magnetometer was later used to map magnetic activity in the ocean floors, providing support to the theory of continental drift.

But we can't print it in a grade 6 science book.


This is what it looks like when it's being used:
Vernon Gerard, peering into a QHM magnetometer on Antarctica in teh 1950s.


Source: Old Antarctic Days.
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