496. When the _earth-element_ originates or separates itself from the water, in order to free itself from all the properties of the latter as well as from those of the air and fire, and to become stiff and solid, the remaining elements exert an incessant influence upon it, and draw a portion of it into their circle, i. e. they confer upon it their properties. a. The Earth-element can be changed by fire Fire-minerals. b. Or changed by air Air-minerals. c. Or changed by water Water-minerals. d. Or lastly, it is severed wholly and substantially } Earth-minerals. free } 497. Through the influx of _fire_ upon the formation of the Earthy it becomes an identical, homogeneous mass, in which the possibility resides, as in the æther itself, of undergoing all changes. This developmental stage of the earth-element is represented by the _metal_. The homogeneous mass of the metal can become earthy by oxydation, aqueous or saline by acidification, aerial or combustible by being hydrogenized. 498. The metal is unanalysable, as is the æther, although it consists of three forms. The metal is easily restored or brought back from its combinations. 499. Besides, however, the identical, homogeneous or simple character, the metal has still also the three characters of fire or of the æther. It is therefore a triplicity in identity. a. In so far as _gravity_ is represented in it, it has the identical or homogeneous mass already indicated, and is heavier than all other bodies. It is central mass. It must be regarded as pure carbon. Metal and the body of gravity are one. b. In so far as light is represented in it, it has the peculiar lustre, which stands again also in intimate connexion with the homogeneous mass. The usual colour of metals is white, the colour of unsullied light. The lustre is properly a self-illumination, and thereupon depends their repulsion of light, or opacity. Metals are therefore adiaphanous or opaque, because they are noncombustible by light. As soon as they become decomposible, namely oxydes, they become also transparent. The metals are the only opaque bodies, because they alone are non-decomposible. All matters become only opaque by admixture with metal, or in so far as the metallic body resides at the bottom of all. The visibility of the world is based upon its metallic character. Without metal we would see nothing. c. In so far as _heat_ is represented in metal is it extensible, fusible and fluidifiable. Metal is water that has become dense.