>build a perfectly flat metal beam several miles long
>lay it over floating platforms on a lake
>reduce the buoyancy of the platforms in the middle ensuring they still make contact with the beam
>measure how much the platforms in the middle have sunk
>finally know the true geometric curvature of the earth that has never been measured
>lay it over floating platforms on a lake
>reduce the buoyancy of the platforms in the middle ensuring they still make contact with the beam
>measure how much the platforms in the middle have sunk
>finally know the true geometric curvature of the earth that has never been measured
