This is false, as the equator does not run north-south. The equators is the line that goes all around the planet in equal distance from the two poles: so it runs west-east.
It is true however that it runs roughly through the middle of the continent of Africa, but rather on the west-east axis.
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It's a Sextant
here is a photo of it with full indications
Hope this Helps :)
You would be describing its Longitude because longitude lines go up and down.