That we have begun with the primary rocks of the Grampians, as the most ancient division of systematic lithology, was more with a view to have some ‘principia’ for description than assumptions for theory, and because no geological research has penetrated deeper. The crust of the earth, as far as observation extends, is proved to consist in its lower parts of a series of crystalline rocks, some of which are stratified, and others unstratified, intercalating one with another, and maintaining the same relative position, each to each, as a system, in every region of the globe. Granite, gneiss, micha-schist, quartz-rock, and limestone, constitute these first outwork courses of creation; one uniform cause acting simultaneously over the earth, appears to have placed them all in position; and as no breathing animal or blossoming plant witnessed this morn-dawn of nature, the rocks belonging to the period are termed the primary or azoic series. The fossiliferous deposits follow in their due order of superposition, arranged into groups and systems according to the organic remains by which they are respectively characterized, and preserving, in their geographical distribution, the same uniform and persistent vertical arrangement as the former. Amorphous rocks, of all ages and extent, are distributed among the stratified portions of the crust, whether crystalline or sedimentary, whereby the latter are dislocated and upheaved, and the inequalities of the surface, and all the pleasing diversity of plain, hill, and mountain have been produced. It is the special object of descriptive or phenomenal geology to note all the facts connected with these appearances and changes, to collate and compare them one with another, and finally, to systematize them according to their natural affinities and relations.