XI. The other condition which we had to notice, was the value of the appearance of labor upon architecture. I have spoken of this before;[G] and it is, indeed, one of the most frequent sources of pleasure which belong to the art, always, however, within certain somewhat remarkable limits. For it does not at first appear easily to be explained why labor, as represented by materials of value, should, without sense of wrong or error, bear being wasted; while the waste of actual workmanship is always painful, so soon as it is apparent. But so it is, that, while precious materials may, with a certain profusion and negligence, be employed for the magnificence of what is seldom seen, the work of man cannot be carelessly and idly bestowed, without an immediate sense of wrong; as if the strength of the living creature were never intended by its Maker to be sacrificed in vain, though it is well for us sometimes to part with what we esteem precious of substance, as showing that in such a service it becomes but dross and dust. And in the nice balance between the straitening of effort or enthusiasm on the one hand, and vainly casting it away upon the other, there are more questions than can be met by any but very just and watchful feeling. In general it is less the mere loss of labor that offends us, than the lack of judgment implied by such loss; so that if men confessedly work for work's sake, and it does not appear that they are ignorant where or how to make their labor tell, we shall not be grossly offended. On the contrary, we shall be pleased if the work be lost in carrying out a principle, or in avoiding a deception. It, indeed, is a law properly belonging to another part of our subject, but it may be allowably stated here, that, whenever, by the construction of a building, some parts of it are hidden from the eye which are the continuation of others bearing some consistent ornament, it is not well that the ornament should cease in the parts concealed; credit is given for it, and it should not be deceptively withdrawn: as, for instance, in the sculpture of the backs of the statues of a temple pediment; never, perhaps, to be seen, but yet not lawfully to be left unfinished. And so in the working out of ornaments in dark concealed places, in which it is best to err on the side of completion; and in the carrying round of string courses, and other such continuous work; not but that they may stop sometimes, on the point of going into some palpably impenetrable recess, but then let them stop boldly and markedly, on some distinct terminal ornament, and never be supposed to exist where they do not. The arches of the towers which flank the transepts of Rouen Cathedral have rosette ornaments on their spandrils, on the three visible sides; none on the side towards the roof. The right of this is rather a nice point for question. [G] Mod. Painters, Part I. Sec. 1, Chap. 3.