It is in some measure these peculiarities which have induced not a few authors to describe Notre Dame as a transitional church. In no part of Notre Dame do we more perfectly appreciate the grandeur of the scale of the church than when we stand in the vast double aisles on either side of the nave. With every step we take the view changes. We hesitate to leave the spot upon which we stand lest we should lose its charm, and yet we feel that probably a vista even more beautiful awaits us a few paces beyond. The lines of vast piers seem as if they were consciously engaged in surprising us: now they come together and close the view suddenly, unexpectedly; then they open, revealing a richly furnished altar in, as it were, a colossal frame of masonry. Everywhere the lines of the building strike us as vast, massive, almost elemental, but everywhere there is an ordered, if a somewhat ponderous symmetry. It is strange that there ever was an age in which the innate dignity and majesty of these lines were not felt. Yet so barbarous did the architecture of Notre Dame appear to eighteenth-century eyes, that a desperate attempt was made to hide it. Vast pictures in gilt frames were placed from capital to capital of the main arcade on both sides. In this way the arches were completely hidden, and a square appearance (supposed to suggest the classical) was given to the lowest story. The openings of the triforium were spared, as anything placed in front of them would block the view of the crowds who used to fill the _tribunes_ on state occasions. The nave, however, thus turned into a kind of picture gallery, was considered very satisfactory (see illustration, p. 11). Needless to say, no trace of the pictures now remains, and the great arches are free and open once more. The piers dividing the aisles are not all of the same construction. Round every other pier are grouped monolithic shafts, possessing delicately foliated capitals with moulded abaci. Two shafts, with a single abacus and plinth, alternate with a single shaft. In all there are twelve shafts round the pier. These piers, with their cluster of satellites, contrast finely with the simple cylinders with bold foliated capitals with which they alternate, and lend variety and interest to the arcades (see illustration, p. 23). [Illustration: _Photo_] [_Ed. Hautecœur, Paris._ THE NAVE, NORTH ARCADE.] The vaulting of the aisles is quadripartite, the ribs being strongly marked and possessing carved bosses at the point of intersection. Beyond the outer aisles on each side is a series of chapels, which will be described presently. The accompanying illustrations give a good idea of the piers, capitals and vaulting of this part of the church.