We must see whether the same clock with weights will go faster at the top of a mountain or at the bottom of a mine; it is probable, if the pull of the weights decreases on the mountain and increases in the mine, that the earth has real attraction.

We must see whether the same clock with weights will go faster at the top of a mountain or at the bottom of a mine; it is probable, if the pull of the weights decreases on the mountain and increases in the mine, that the earth has real attraction.