QUOTE : Moreover, do the experiments which are supposed to prove the constant character of the speed oflight really get beyond the earthly sphere, and do they not imply both space and time as usually imagined by us? Thus '300,000 km per second' is stated to be the speed of light, and it is held that here is a value which, if it be not necessarily everywhere expressed in this manner, does nonetheless remain constant throughout the physical universe. The astronomer who counts, by referring to the lines of the spectrum, the light-years separating us from the nebula of Andromeda, supposes without more ado that the universe is every-where 'woven' in the same manner. Now, what would happen if the constant character of the speed of light ever came to be doubted and there is every likelihood that it will be sooner or later so that the only fixed pivot of Einstein's theory would fall down? The whole modern conception of the universe would immediately dissolve like a mirage.