Page:Geology and Mineralogy considered with reference to Natural Theology, 1837, volume 1.djvu/433

 Rh fortuitously have settled into any of those under which it actually appears. Now, on this hypothesis, we ought to find all kinds of substances presented occasionally under an infinite number of external forms, and combined in endless varieties of indefinite proportions; but observation has shown that crystalline mineral bodies occur under a fixed and limited number of external forms called secondary, and that these are constructed on a series of more simple primary forms, which are demonstrable by cleavage and mechanical division, without chemical analysis: the integrant molecules of these primary forms of crystals are usually compound bodies, made up of an ulterior series of constituent molecules, i. e. molecules of the first substances obtained by chemical analysis; and these in many cases are also compound bodies, made up of the elementary molecules, or final indivisible atoms, of which the ultimate particles of matter are probably composed.