347. Co-illuminating bodies are thus analogous still to the æther. If there are non-transparent bodies, they can only be found in the earth-element, which, being furthest removed from the æther, has perfected itself independently, and they must indeed be wholly deoxydised.
348. The co-illumination of bodies or their transparency is an effort of deoxydation. Bodies that cannot at all be deoxydised are non-transparent.
REFLEXION.
349. Transparency belongs only to those bodies which have in themselves a twofold character. It will be shown that the metals are absolutely identical matters, and therefore non-transparent. The metals are the only non-transparent bodies. Metaleity = non-transparency.
350. The light falls upon a non-transparent only through a transparent body, and thus one in which the tension of light propagates itself. This co-illumination of the matter placed in front of the non-transparent body cannot cease to co-illuminate; the tension must thus abide in it, and turn back from the non-transparent body, in a straight direction if the tension fell direct upon it, at a certain angle, if obliquely. This phenomenon is called Reflexion.
351. Reflexion is no repulsion of light, but only its tension continued into the medium, in which the tension has been.
352. A non-transparent body indicates nothing for the tension of light but the limit of the co-illuminating matter; it does not at all operate itself upon the light, it is as it were a void space.
353. Transparent bodies also reflect partly, because they are only relative æther, because they only co-illuminate, are not themselves tensed; or because the basis in all is the metal. Every other medium is, however, an æther differently fixed; in every one therefore the tension has been changed; every medium is thus a limit for the tension, and therefore the transparent bodies also reflect. Since the tension becomes altered, when it passes into another medium, it always remains by preference in the neutral medium; therefore reflexion originates also by the air, when the light passes out of glass very obliquely into it.
Operation of the terrestrial Elements upon Light.
DECOMPOSITION OF LIGHT—COLOURS.