There is no aberration of terrestrial sources, because the light-vector has an inertial component. A new analysis of the Michelson Morley experiment shows: Light propagates anisotropically relative to a moving system, dependent on the velocity and the angle between the velocity and the direction of motion. The two way (back and forth) velocity is isotropic, but also dependent on the velocity of the frame. There is no Lorentz contraction. - A real ultrasonic experiment shows: Also the propagation of sound follows the given general conical section equation and an acoustical Michelson Morley experiment gives the same zero result as the optical experiment in contrast to the school of thought. - The theory of relativity is incorrect and the existence of a luminiferous ether as a propagation medium and an absolute frame of reference is again obvious. Some properties of the ether and a fundamental cause of the dependency of the velocity on the mass and the frequency are presented.