compass

The flight carried an instrument that shines lasers at atoms, which behave like compass needles to measure Earth’s magnetic field in real time.

It was like the needle of a compass pointing at the heavens.

Alexander had drawn a map of the nursery, tinted with watercolors and oriented according to the compass, with all the furniture drawn to scale, down to the last footstool.

This was at Alexander’s request; he was quite taken with the topic of navigation all of a sudden and refused to go ten steps in any direction without referring to his compass.

I taught them how to use rulers, compasses, protractors, and triangular scales.