There is a real logical incoherence in a good many expositions of the Theory of Relativity. The Lorentz-Fitzgerald contraction and the slowing of the clocks on a moving platform are first introduced as physical changes due to absolute motion. In the purely dynamical arguments between Absolutists and Relationists the Absolutist staked his case on absolute acceleration and absolute rotation. The new sciences which have developed since Newton's time leave the question between the Absolutists and the Relationists exactly where it was. The velocity of light is something that has been experimentally measured, and what has been measured must have been the time that a wave of light took to get from one body to another. Similarly the laws of electro-magnetics were discovered and verified by experiments on bodies, and the velocities that were observed were the velocities of these bodies relative to others.