§ IX. The science of this arrangement has made it the subject of much enthusiastic declamation among the Gothic architects, almost as unreasonable, in some respects, as the declamation of the Renaissance architects respecting Greek structure. The fact is, that the whole northern buttress system is based on the grand requirement of tall windows and vast masses of light at the end of the apse. In order to gain this quantity of light, the piers between the windows are diminished in thickness until they are far too weak to bear the roof, and then sustained by external buttresses. In the Italian method the light is rather dreaded than desired, and the wall is made wide enough between the windows to bear the roof, and so left. In fact, the simplest expression of the difference in the systems is, that a northern apse is a southern one with its inter-fenestrial piers set edgeways. Thus, _a_, Fig. XLII., is the general idea of the southern apse; take it to pieces, and set all its piers edgeways, as at _b_, and you have the northern one. You gain much light for the interior, but you cut the exterior to pieces, and instead of a bold rounded or polygonal surface, ready for any kind of decoration, you have a series of dark and damp cells, which no device that I have yet seen has succeeded in decorating in a perfectly satisfactory manner. If the system be farther carried, and a second or third order of buttresses be added, the real fact is that we have a building standing on two or three rows of concentric piers, with the _roof off_ the whole of it except the central circle, and only ribs left, to carry the weight of the bit of remaining roof in the middle; and after the eye has been accustomed to the bold and simple rounding of the Italian apse, the skeleton character of the disposition is painfully felt. After spending some months in Venice, I thought Bourges Cathedral looked exactly like a half-built ship on its shores. It is useless, however, to dispute respecting the merits of the two systems: both are noble in their place; the Northern decidedly the most scientific, or at least involving the greatest display of science, the Italian the calmest and purest, this having in it the sublimity of a calm heaven or a windless noon, the other that of a mountain flank tormented by the north wind, and withering into grisly furrows of alternate chasm and crag.