477. The changes of the earth-element can only take place upon its fundamental or characteristic body, thus on carbon. 478. Nothing can, however, change of itself. All change must proceed from external influence. All things can be changed therefore by such influences only as are already antecedent to or _before_ them. The two other bodies, however, are prior to carbon; before the earth-element only the three other elements. 479. The earth can therefore be changed in only two ways; either the carbon by the other elemental bodies, or the total earth-element by the other elements. 480. The changes wrought by the influence of these bodies are, however, only partial or fractional changes. Therefore partial or chemical diversities only originate, and with them other different bodies or degrees of such. The changes effected by the elements are, however, total changes, which bear not only reference to the carbon, but to all the constituent parts of the earth-element. 481. Total changes or different conditions of the earth-element are called _Minerals_, or earths. 482. The _genesis_ of minerals, thus their collective character, as differently posited fixations of earth, determines the classes, orders, and genera. 483. The _genus_ is the product of a genetic moment, and is therefore always a definite, chemical mixture, which alone consequently expresses the essential character. Hitherto there has been no definition of mineral genera. 484. _Species_ of minerals are successive developments of the genetic moment, thus stöchiometric subdivisions of the genetic mixture, e. g. the different degrees of oxydation of nitrogen, in the oxyde, binoxyde gases and nitric acid. Hitherto it was not known what a mineral species might be; Physio-philosophy has been the first to introduce clearness to these conceptions. 485. A stöchiometric mixture in the earth-element is an individual. 486. Individuals only are the object of natural history, and thus neither water, air, nor fire. This also was not known previous to Physio-philosophy; it is, however, gradually acknowledged also by empirics. 487. The crystalline form is merely an external character for the species, and therefore the same nuclei may occur in the different orders. 488. Kinds or _varieties_ are different conditions of cohesion. They are therefore not determined by the form of the secondary crystal, since the aberration of forms results only from a stoppage upon their part half way or from the quantitative energy of the polar radii or polar axes.