726. Moreover, as the ores occur only in narrow spaces with their vein-stones and both form alternating tables upon the walls of the veins, they must have been attracted by the latter. 727. The walls of the vein consequently exert a polar influence upon the ore and vein-stone. Now, if this be their mode of action, they must be in a condition to separate the fundamental mass. 728. It is thus the vein themselves, which, by a vital force, produce the metals; they are thus a living womb, or matrix as it has been emphatically termed. 729. Two walls in close juxtaposition are requisite for the production of metal. Upon a freely exposed wall or face of rock no metals are found. 730. By this separation, however, two kinds of minerals originate, Inflammables, and ores proper or metals. The action of the walls must be therefore of a twofold nature. 731. But two cases also are conceivable, in accordance wherewith this polarity of the vein admits of being divided. It subsists either quite alone between the two walls, as surface-polarity or electricity; or it subsists between the mediate point of the earth and the walls, constituting centroperipheric polarity or magnetism. 732. The product of the surface polarity are the Inflammables, of the radial polarity the metals. 733. Since no more metals and Inflammables originate at the present day, although magnetism and electricity are in continual operation; a third influence moreover must have been in constant activity. Now this cannot be thought of as any other than _heat_. The metals must thus have originated while the earth was still in a glowing state, and when thus also magnetism and electricity could operate more powerfully towards effecting a reduction of the mass. By heat the mass in the veins was probably converted into gas, through which its separation by means of magnetism and electricity into ore and transition earth could more easily take place. The metals are thus sublimations, which were first deposited, when the earths or rather the mountain-stock began to cool. Thus also zeolithic crystals were deposited in the upper stores of mines. Metals are thus the children of heat, of magnetism and electricity; the heat renders the mass in a fit state for being separated in the next place by the polar forces. 734. Metal is carbon completely reduced, which contains nothing more of the other elements in itself, namely, neither hydrogen nor oxygen. It is consequently the Basic of the earth-element without material admixture, and thus is earth with the properties of its prototype, of fire or of gravity, of light and of heat. 735. In accordance with this interpretation metal can be produced by no other process than the centro-peripheric. Its occurrence in fissures of the earth that are mostly perpendicular likewise proves this.