Series of experiments on the sedimentation of a variety of isometrically-shaped bodies are described and it is shown that the resistance to motion R, of a body moving with velocity v, in an infinite extent of fluid in the region of streamline flow is given by R = vηK√(surface area of body), where η is the viscosity of the fluid and K a shape factor of the particle which varies from ³√π for spheres to ³√2.92 for tetrahedra. By using a value of ³√3 for K the equation may be applied to isometric and other compact shapes, where the axial ratio does not exceed about 1.4 to 1, with an error not greater than ±2%.A more accurate, but less easily applied, empirical relationship for the settling rate of compact bodies is also given and an equation which satisfies the interference effects of the walls of a sedimentation vessel upon a falling body is developed experimentally.