580. Whatever be the bulk of the mass of water, to the same extent is the Earthy, or the germ of the Earthy, diffused throughout it. The whole is a fluid mass of earth. Light, however, penetrates the mass of water as a transparent body. As translucency is not a mechanical but a dynamic act, or process of differentialization in matter; so does this earth-water become separated into a mass of oxygen and carbon, or into ordinary water and into the earth-element. 581. The genesis of the earths is a process of conduction of light. All transparency is a formation of earth; for it is a separation of the Aqueous from the body of gravity. Where non-transparency exists, there has earth been already formed. 582. As the conducting process of light is an act of deoxydation, so are the earths at the same time also deoxydized by precipitation, and this in four stages which indicate the elements whereby light operates upon the Basic in water; or it might be said, by the four colours of, or by coloured, light. We already know that the earth, which presents in itself the most dismembered character is the calcareous earth; but that those which have preserved a more identical character in themselves are the silicious, argillaceous, and talcose earths. These earths may be viewed as those in which the lime has absorbed a proportion of oxygen, which has in it become carbonic acid. There is indeed only _one_ earth-substance in water. In this substance, which is neither silex nor calx, the polar principle has distributed itself, and that very portion, which has obtained the most thereof, has become calcareous earth. 583. The calcareous earth has originated in the upper parts of the aqueous globe, the other earths, however, in the depths, in the middle of that globe; for in the upper regions of the water, the light can exert a greater polarizing influence, and therefore that very earth is generated which stands nearest to the æther or to the light, viz. the different calcareous earth. But in the depths of the water, the light loses its energy, and is no longer in a condition to elicit the Oxygenous in the Basic; thereby identical and more fixed earths originate. GRANULAR ROCK OR GRANITE. 584. The differenced calcareous earth has been associated with the differential water, remained for a longer period identical with and dissolved in it, and was therefore the last to be precipitated from it. The silicious earth with its neighbours must necessarily have been the first to separate from the water, as it is in a proper sense, that earth from which all water has been withdrawn. Two periods of precipitation exist therefore in geogeny, one that of the identical or fundamental earths, and one of the internally subdivided calcareous earths.