WEIGHT (in Physics.) A quality in na tural bodies, by which they tend towards the centre of the earth. Weight may be distin guished into absolute, specific, and relative. It is demonstrated by Sir Isaac Newton, I. That the weights of all bodies at equal distan ces from the centre of the earth, are propor tional to the quantities of matter that each con tains. 2. On different parts at the earth's sur face, the weight of the same body is different, owing to the spheroidal figure of the earth, which causes the bodies on the surface to be nearer the centre in going from the equator to wards the poles ; and the increase of weight is nearly in proportion to the square of the sine of the latitude; the weight at the equator to that at thepole being as 229 :230, or the whole increase of weight from the equator to the pole is the 229th part of the former. 3. That the weights of the same body, at different distances above the earth, are inversely as the squares of the distances from the centre. So that a
body at the distance of the moon, which is 60 semidiameters from the earth's centre, would weigh only one thirty-six thousandth part of what it weighs at the surface of the earth. 4. That at different distances within the earth, or below the surface, the weights of the same body are directly as the distances from the earth's centre ; so that half way toward the centre of a body it would weigh but half as much, and at the centre it would weigh nothing at all. 5. A body immersed in a fluid, which is specifically lighter than itself, loses so much of its weight as is equal to the weight of a quantity of the fluid of the same bulk with it self. Hence a body loses more of its weight in a heavier fluid than in lighter one, add, therefore, it weighs more in alighter fluid than in a heavier one.
A gallon of oil weighs 71 lbs.
A cubic foot of water 1000 ox.
A pint of water 16 ea.