The Weight of the Earth

Abstract

IN a letter in this week's NATURE, signed “The Reviewer,” the writer does not notice that in the English language, and in all legal and common usages of it, including that of all scientific men in speaking of their weighings by ordinary balances, weights mean masses. The fact that the weight of the earth is 6˙14 × 10²¹ tons is as clear as that the weight of a parcel of tea is 3 lb. It is the heaviness of a weight or mass that if a property accidental to its position, being less at the equator, greater at the poles, and nothing at the earth's centre. I have never yet heard a “bòx of weights” called a box of masses. I don't believe even “The Reviewer” calls it a box of masses. If carried to the centre of the earth it is still a box of weights, though the heaviness of the weights is zero.