much the permanence, as well as propriety, of structure depended on the stones being couchant in the wall, as they had been in the quarry: to which subject I wish to-day to direct your attention.
141. You will find stated with as much clearness as I am able, in the first and fifth lectures in "Aratra Pentelici," the principles of architectural design to which, in all my future teaching, I shall have constantly to appeal; namely, that architecture consists distinctively in the adaptation of form to resist force;—that, practically, it may be always thought of as doing this by the ingenious adjustment of various pieces of solid material; that the perception of this ingenious adjustment, or structure, is to be always joined with our admiration of the superadded ornament; and that all delightful ornament is the honouring of such useful structures; but that the beauty of the ornament itself is independent of the structure, and arrived at by powers of mind of a very different class from those which are necessary to give skill in architecture proper.
142. During the course of this last summer I have been myself very directly interested in some of the quite elementary processes of true