SRT is known to rest upon two basic postulates: (1) light-speed constancy, and (2) the principle of relativity, which is extrapolated to electromagnetic phenomena. One of the main proofs of the validity of light-speed constancy lies in negative results of experiments on observing the ether wind. We shall see below what should be obtained from the experiments by Michelson - Morley and other researchers from the viewpoint of empty space (more precise from Galileo's relativity principle). Note that we cannot suppose in advance anything about the motion of the Earth; at Galileo's time, for example, such experiments would prove that the Earth was resting. Generally speaking, before using a "device", the latter must be tested and graduated under laboratory conditions -- we must know what can be measured by it? (But the present situation was as in the anecdote: -"Test device, Pete", -"Three!", -"What means "three"?", -"But ... what is a device like?") Imagine that somebody were create the following "theory": due to the Earth's axial rotation a constant wind with the value of about 400 m/s might be observed along terrestrial parallels. Measuring it by weathercocks with rotators, it would be obtained that the wind is permanently varying within the broad limits both in the direction and in the value depending on time and place. The "conclusion" would be made from this that the atmosphere is absent at the Earth at all. Since the book is specifically devoted to the criticism of the relativity theory, we will primarily broach the conventional modern relativistic concepts, though some ether concepts will briefly be outlined also.