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OP THE MENSURATION

It is well known, that if an uniform beam, orrod, be suspended in the middle, and left atrest, the cords which sustain the equal scales, orweights, that are hung at its two extremities,will take such situations as are perpendicular tothe horizon ; or, which is the fame thing, suchas tend directly towards the center of the earth.But if a circular motion be given to this ba-lance, the center of which is the point of thebeam’s suspension, the scales will immediatelyfly out of the perpendicular lines, in proportionto the velocity of the circular motion; so thatthe cords will no longer follow the usual direc-tion of gravity, towards the center of the earth,but will take such oblique situations, that thescales, or lower extremities, will be farther apartthan any other two corresponding points of thecords.

This illustration is applied by M. Voltaire tothe figure of the earth, Let us conceive, fayshe, a large balance, whose middle is suspendedat one of the poles, and whose extremities, orweights, extend to an equal elevation on eachfide of the equator ; then it is evident, that ifthe earth, which we are now examining, turnsupon its axis, and carries this balance roundwith it, by a circular motion, the cords, towhich the weights are appended, will be re-moved from their former situation, out of theperpendicular lines on both sides, and will fly4 . Off