It may be said that these joints were invisible until the passage of centuries had laid them bare by destroying the stucco which, especially where sandstone or limestone was used, once veiled the surface of the bare walls.[112] Doubtless this is true; but even in a climate such as that of Egypt, the architect could not believe that a thin coat of plaster would endure as long as the massive walls upon which he laid it. We have here a great contrast in principle between the decoration and the architecture of Egypt. In the latter the chief, if not the only aim, seems to have been to make sure of absolute stability, of indefinite duration; and yet these eternal walls are lined with a rich decoration which is spoiled by the fall of a piece of plaster, which is injured by the unavoidable settlings of the masonry and destroyed by the slightest earthquake! Of this we need give but one conclusive instance. Our third plate reproduces that admirable portrait of Seti I., which is the wonder of the temple at Abydos. This beautiful work in relief is sculptured upon the internal faces of four unequal stones in the wall of one of the rooms. The joints may be distinguished, but as yet they have not opened sufficiently to do much damage to the artistic beauty of the work; but it cannot be denied that the preservation of the royal effigy would have been much more certainly assured if the sculptor had chosen a single stone to work upon, instead of a built-up wall which so many causes would help to destroy.