Had the Romans at this period been more desirous to improve their external architecture, there is little doubt that they would have adopted the expedient of omitting the entire entablature: but at this time almost all their efforts were devoted to internal improvement, and not unfrequently at the expense of the exterior. Indeed the whole history of Roman art, from the time of Augustus to that of Constantine, is a transition from the external architecture of the Greeks to the internal embellishment of the Christians. At first we see the cells of the temple gradually enlarged at the expense of the peristyle, and finally, in some instances, entirely overpowering them. Their basilicas and halls become more important than their porticoes, and the exterior is in almost every instance sacrificed to internal arrangements. For an interior, an arch resting on a circular column is obviously far more appropriate than one resting on a pier. Externally, on the contrary, the square pier is most suitable, because a pillar cannot support a wall of sufficient thickness. This defect was not remedied until the Gothic architects devised the plan of coupling two or more pillars together; but this point had not been reached at the time when with the fall of Rome all progress in art was effectually checked for a time. TEMPLES. There is perhaps nothing that strikes the inquirer into the architectural history of Rome more than the extreme insignificance of her temples, as compared with the other buildings of the imperial city and with some contemporary temples found in the provinces. The only temple which remains at all worthy of such a capital is the Pantheon. All others are now mere fragments, from which we can with difficulty restore even the plans of the buildings, far less judge of their effect. We have now no means of forming an opinion of the great national temple of the Capitoline Jove, no trace of it, nor any intelligible description, having been preserved to the present time. Its having been of Etruscan origin, and retaining its original form to the latest day, would lead us to suppose that the temple itself was small, and that its magnificence, if any, was confined to the enclosure and to the substructure, which may have been immense. Of the Augustan age we have nothing but the remains of three temples, each consisting of only three columns; and the excavations that have been made around them have not sufficed to make even their plans tolerably clear.