For demonstrating Archimedes law. Consists of a plastic weight with an eye and a transparent plastic container with two nylon loops: The upper loop is for suspension from a dynamometer or a balance, while the weight hangs from the lower loop. The plastic weight is immersed in water and therefore subject to buoyancy equivalent to the weight of the displaced volume of liquid. The buoyancy is compensated for by filling the plastic container with water. The inner volume of the container equals the volume of the plastic weight.