§ =82.= The analysis of matter has been carried a step further. A philosophical view of the Cosmos involves the assumption of an absolutely continuous and homogeneous medium filling all space, for an absolute vacuum is unthinkable, and if it were supposed that the stuff filling all space is of an atomic structure, the question arises, What occupies the interstices between its atoms? This ubiquitous medium is termed by the scientists of to-day “the Ether of Space.” Moreover, such a medium as the Ether is demanded by the phenomena of light. It appears, however, that the ether of space has another and a still more important function than the transmission of light: the idea that matter has its explanation therein has been developed by Sir Oliver Lodge. The evidence certainly points to the conclusion that matter is some sort of singularity in the ether, probably a stress centre. We have been too much accustomed to think of the ether as something excessively light and quite the reverse of massive or dense, in which it appears we have been wrong. Sir Oliver Lodge calculates that the density of the ether is far greater than that of the most dense forms of matter; not that matter is to be thought of as a rarefaction of the ether, for the ether within matter is as dense as that without. What we call matter, however, is not a continuous substance; it consists, rather, of a number of widely separated particles, whence its comparatively small density compared with the perfectly continuous ether. Further, if there is a difficulty in conceiving how a perfect fluid like the ether can give rise to a solid body possessed of such properties as rigidity, impenetrability and elasticity, we must remember that all these properties can be produced by means of motion. A jet of water moving with a sufficient velocity behaves like a rigid and impenetrable solid, whilst a revolving disc of paper exhibits elasticity and can act as a circular saw.[97] It appears, therefore, that the ancient doctrine of the alchemistic essence is fundamentally true after all, that out of the “One Thing” all material things have been produced by adaptation or modification; and, as we have already noticed (§ 60), there also appears to be some resemblance between the concept of the electron and that of the seed of gold, which seed, it should be borne in mind, was regarded by the alchemists as the common seed of all metals. [97] See Sir OLIVER LODGE, F.R.S.: _The Ether of Space_ (1909). Further Evidence of the Complexity of the Atoms.