The transformation of the Choir, with its transeptal chapels, into the Decorated style, was now complete. I have throughout spoken of the work as a transformation, and not a re-building in the strict sense: because I consider that the evidence for that fact is, though not obvious, perfectly irresistible. It may be well to note here the chief elements of proof.
There is then, first, the parallel case of other Cathedrals, in which transformations, no less vast, and perfectly discernible, have unquestionably been made. At Winchester (as Professor Willis acutely discerned, and fully proved), the huge Norman Nave was transformed into Perpendicular by William of Wykeham, without pulling down a pillar of it. At Gloucester, again, in the Choir, the superinduced Perpendicular work hangs visibly, like a robe, upon the original Norman body.
But next, the fact of some degree of transformation in our own Cathedral is palpable, and cannot be called in question. No one doubts that the towers are Norman towers; so that their present Decorated aspect, internally, is due to transformation. Bishop Quivil, and in some degree Marshall before him, certainly initiated a policy of transformation here. They decided, that is, that it was better, as far as these towers were concerned, to remodel them, than to pull them down. The only question is, How far did Quivil and others carry on the work of remodelling, in lieu of rebuilding? And this, of course, depends in part on other questions, viz., How much was there for them to remodel? Was there really an older Choir or Nave? What proof have we that these were ever completed at all, before the Decorated period? Or if they were, were they not entirely pulled down then? There is not, to the eye of the superficial observer, nor even to the more practised eye at first sight, any appearance of their framework having been utilised, as in the case of the towers, by the Decorated builders. Nevertheless, as I have said, the proof is really incontrovertible: and the fact, once ascertained, is the key to the whole architectural history of the present Cathedral.
It was reserved for the acumen of Professor Willis, on the occasion of the meeting of the British Association at Exeter, to detect one certain proof of transformation, as distinguished from re-erection, in the Choir walls. That proof, with others to be adduced hereafter, rests on the obvious presumption, that no architect will willingly go out of his way to encumber himself with difficulties of his own creating. When we find that the harmony and correspondence which the eye expects in architecture, and which is nowhere more completely realized than here, was only attained by a number of ingenious artifices, as of masking and getting over certain inequalities and discrepancies, then we may be sure that these latter were none of the architect's making; but that he found them existing and was under the necessity of dealing with them as he best could. No one, e.g. would voluntarily carry on a wall at a certain thickness to a certain point, and then suddenly make it a foot thinner, thereby involving himself in serious difficulties in the endeavour to make all look even and harmonious to the eye.
Applying this test to our Choir walls and arches, as they are, we see at once, when it is pointed out, that the existing difference of depth between that part of the clerestory arcade which rest on the three western arches, and that which rests on the four eastern ones, was necessitated by a sudden diminution in the thickness of the wall. The Norman Choir had evidently only extended, as usual, to three bays; and Marshall, in making his additions eastward, had not cared to make his walls so thick as the Norman ones. Hence the difference and the difficulty: a difficuly so great that, as I have shown above, Bitton was induced by it to omit the arcading in the eastern part altogether. But Stapeldon, struck with the unsatisfactory appearance of its breaking off suddenly at the very point where ornament was most in place, determined to carry it through to the east end. And so felicitously is it done, that it is only on a second examination that the difference of depth in the arcading makes itself noticeable. As seen from the choir entrance, it appears as if the difference was due to the distance and the perspective. (45)
The same is the case with the pillars of the eastern portion or presbytery, as compared with those of the western portion; and from the same cause. Here, too, the difficulty arising from the sudden diminution in the thickness of the wall had to be faced and dealt with. The difference in the diameter of the pillars in the presbytery and in the chorus cantorum is accordingly about nine inches; in their circumference, two feet. But here, again, the inner line, as seen from the choir entrance, being unbroken, the discrepancy is not perceived. In the aisle the line is, of course, broken; but there it is of less consequence. The only real difficulty that arose was about the western half of the last pair of presbytery arches. The spread of the western pair of capitals being larger than that of the eastern, an awkward projection would have been the result. But a stilt or strut rising from the edge of the capital meets the arch and gets over the difficulty.
Such are the expedients by which our builders overcame perplexities arising, we cannot doubt, from the fact of their retaining and utilising the old walling.
And what puts beyond all doubt the fact of their having retained it, is that it has been found by the workmen, on removing the old coating of wash from the vaulting ribs, that the earlier ribbing, of Marshall's date, had been up to a certain point retained. Four or five feet were added to the height of the vault, and a new curve taken. But the earlier springing was preserved, with the necessary adaptation.