“The centre of gravity of any hemisphere [is on the straight line which] is its axis, and divides the said straight line in such a way that the portion of it adjacent to the surface of the hemisphere has to the remaining portion the ratio which 5 has to 3.”

—  Archimedes, book The Method of Mechanical Theorems

Proposition 6.
The Method of Mechanical Theorems

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Greek mathematician, physicist, engineer, inventor, and ast… -287–-212 BC

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