§ 3. ORIGINAL FORM OF THE CHURCH.
Dome, &c.—Agathias tells us that when Justinian rebuilt the dome it was made higher, and that large alterations were made to the sustaining arches on the north and south sides. Salzenberg cites Theophanes and Zonaras who give the increase of height as twenty and twenty-five feet respectively. If we examine the longitudinal section we shall see that the great semidomes of the hemicycles and the apsoid of the bema show much less of their curvature outside than the present central dome. The windows in these do not stand above a cornice, but are pierced through the vaults at middle height; the domical surface being unbroken by any cornice from springing to crown. The cupola of the baptistery is also continuous with the pendentives. A dome of this kind, however, continuing the pendentives, would seem to be impossibly flat, and would be some thirty feet less than the present height—see A in [Fig. 4], the existing dome rising to B. If a curve between these two be obtained by lowering the crown of the dome about fifteen feet to C, it may be noticed that a straight line tangential to the curve of the eastern apsoid, and also to the great semidome would form similar contact with the dome.
Salzenberg, understanding an account of Cedrenus as to a strengthening of the abutments of the dome to refer to the great buttress masses which rise above the gynaeceum roof, considers that the external parts of these masses were additions made at the time of Justinian’s restoration. These great vertical piles are so essential to the structure, to the logical beauty of the design, and to the staircase service of the building; moreover the preparation for them beneath is so adequate, that we cannot accept this suggestion, and therefore follow Choisy in considering them original. Now Choisy, examining the external base of the dome where it forms a square, found that the four angles had been increased, and that it did not originally form a square, but rose above the piers and the lateral arches as shown in [Fig. 34], and in [Fig. 37], where the first base is shown by hatching and the additions by dotted lines, A A. “This alteration,” he writes, “is not hypothetical. I verified the entire absence of bond between the first base of the dome and the added work” (p. 138). These additions were built on the lateral arches, and on the top of the piers, altering the form shown in our [Fig. 35] to the present form given by Salzenberg. That Choisy is right, is borne out by seeing the resemblance of treatment that there would have been between the growth of the dome on the north and south and the semidome on the west (see [Fig. 34]).
Fig. 34.—View of Vaulted System of S. Sophia, adapted from Choisy.
Again, Salzenberg hardly makes it sufficiently clear that the large arches in the walls which fill the great vertical semicircles over the arcades on north and south sides, are in fact the inner surfaces of the arches which pass between the pairs of piers on north and south sides (seventy-two feet apart in this direction), and being the whole width of those piers (fifteen feet eight inches) on soffite they form the immense arches so well known on the outside. The semicircles of wall, each of which contains twelve windows, are now filled in beneath these arches, flush with their inner faces, and the arches therefore do not show to the interior through the decoration (Figs. [4], [36], [38]).
Fig. 35.—Plan of Upper Gallery as first designed.
Fig. 36.—Section of Aisles and Gallery.
Now Agathias (see page [30]) says that at the restoration after the earthquake in 558, at the north and south arches they brought towards the inside “the portion of the building which was on the curve.” This, we think, must refer to the filling wall, in the arches of seventy-two feet span, which we suppose was formerly on the exterior, and thus left an upper gallery twelve feet wide and seventy-two feet long open to the interior. “And they made the arches wider to be in harmony with the others, thus making the equilateral symmetry more perfect. They thus reduced the vast space and formed an oblong design.” That is the arches of seventy-two feet, when filled up on the inside, were no longer visible, and the dome appeared to stand over arches of 100 feet span on north and south, as already on east and west, the transverse dimension of the church being lessened between these points by some twenty-four feet. Salzenberg understanding Agathias to refer to the apparent arches of 100 feet span on north and south is unable to offer any explanation.
Fig. 37.—Plan of Basis of Dome as originally designed, with Additions A A containing stairs.
Fig. 38.—Section between Great and Secondary Orders.
The actual evidence in the church, we believe, fully bears out the interpretation here suggested. What we have called the secondary order of columns would pass exactly beneath the position given to this wall. These columns on the gallery floor are very strong, and a very strong row of arches runs along over them (see [Fig. 38]). Moreover the curtain walls in every other instance throughout the church are flush with the exterior.
That this space is not available to the interior of S. Sophia has caused Choisy to criticise the design in this respect as “a solution undecided, moyen terme, fâcheux; the large arches by a departure from ordinary rule being thrown on the outside so that the space covered by them was lost. S. Sophia Salonica redressed this error.” We wonder that Choisy’s views as to the original base of the dome did not cause him to take the further step we have here suggested. The present form, in which the lateral arches support the square base of the dome, is at least a possible one; but that the arches when they carried nothing and thus were actually vaults (as before shown by Choisy) were not filled with a screen but were mere arches twelve feet on soffite, lying against the sides of the building seems inconceivable. In our [Figure 34] we have amended Choisy’s view in this respect. Looking on these lateral arches as vaults we have filled them with a window like the western vault, and the harmony which results between the sides and the west end amply verifies our conclusions. One point further. The upper surface of the base of the dome on the west side should not be wholly level as shown in [Fig. 34], the central third curves up following the line of the top of semidome. In other words, the great arch of the interior pushes itself up through the base of the dome, and this treatment thus recurred at various heights—over large windows of aisles, over western and lateral lunettes, as we have shown, and over the semidome.
Originally, before the interior was narrowed in the way we have explained, there was a much clearer suggestion of a cross plan: barrel vaults at north and south being filled at their ends with large lunettes like the west vault. We suppose that the failure was mainly in the secondary order, and that the window screen and all possible weight was entirely removed and transferred to the great order. Salzenberg was satisfied that there had been great alterations in this part of the building, and Choisy’s view of the window-wall, Plate xxv., entirely confirms his opinion. If it could be shown that the alteration spoken of by Agathias will not bear the interpretation we put on it, there were earlier troubles at this part mentioned by Procopius. The best proof, however, we suggest is found in the design. It has been before pointed out that Choisy and other writers have too hastily assumed that S. Sophia Salonica was built after the great church of Constantinople. That it preceded it enforces the present argument. Grelot (1680) writes that upper galleries remained in the church in these positions, but he based his assertion on the row of seven arched recesses just above the main cornice which he thought were formerly open. It is clear however from an examination of the section that the arches could only have opened to the vault of the first floor gynaeceum. That these small arches did open to the vault of the first floor, seems to be borne out by the fact that above the centre of the secondary order, where its arch is low, a similar piercing is made, through which (or the higher arches on each side) and through the seven arches, a mysterious perspective into the immensity of the dome might have been obtained by those in the gynaeceum (see Figs. [4], [36], [38]). Shallow arched recesses merely used decoratively seem to have been little known to early Byzantine art, and arches on the first floor through the great piers are blocked in a similar way. Moreover such openings would explain why the vault between the two orders of columns is so much stilted up into mere darkness.
Atrium.—To explain the present confused arrangement of the exterior, we must remember that from the time of the description of the church by the Silentiary to its description by Gyllius was a thousand years—as long as from the time of Alfred to the present day—and in this time we may well expect alterations and accretions.
In Chapter IX. we have shown that the present form of the exonarthex, with its great external piers, was an alteration, made about the time the belfry was added in the ninth century. Before that time the atrium was alike on all four sides—a true quadriporticus—one of the most beautiful features of the ancient churches. (See Figs. [3] and [25].)
North and South Porches.—Much of the confusion at the north-west and south-west angles is the result of Turkish attachments, including the western minarets, which were built in the last quarter of the sixteenth century. The plan of gynaeceum floor furnishes the best key to the former arrangement, for where there is Byzantine work above, it must once have existed below. Comparing the first floor and roof plans in Salzenberg with the ground plan, it becomes apparent that the main block was originally finished both at north-west and south-west angles to the general square of building. The two staircases now at these angles were added as extra buttressing masses; the original stairs being the four in the piers of north and south sides. The north and south porches, with extra building above the latter on the first floor, were also additions. Besides the irregularity and inferior style of these buildings the following evidence should be noticed. The actual form of the north-west angle on the gallery floor; and the natural reading of the three plans when laid one over the other; broad arches, which pass across the porches; the fact that the arch in south porch (dotted in C on [Figure 24], see also Fossati, Plate i.) now has no office; and that above the door at this end of narthex, there is a window which now merely opens into the south porch.
An examination of the exterior on the south side shows that the south-west staircase was built before the porch, or the part above it at least, because a straight joint in the walling, and the form of the roofing, here clearly make evident that the apex of the gable roof was originally over the centre of the staircase, and that the slope has been subsequently run forward to cover the part above the porch.
In considering all the other irregularly attached buildings, together with the historical evidence, it seems clear that the church as designed and first built was externally a regular parallelogram, interrupted only by the projection of the apse at the east end; which was itself masked by a range of low chambers against the east wall, through which there were two entrances to the church as at present, and to which other two doors, in the east wall, still visible but now blocked, gave access. The other external doors, besides those from narthex, being two on the north and one in the south wall; together with two external doors at the gynaeceum level, one of which probably gave access to the gallery along which the emperor passed to the church, and the other, to the north, may have led to the cells of the clergy.
Baptistery and Loggia.—Of early buildings detached from the church we have the round building at the north-east, which we regard as having descended from the earlier church, and the south-west baptistery, with a loggia attached to its north side. The space between the church and the baptistery on plan looks like a covered way, leading from the church with a screen in the middle, but the part next the church is, and always must have been, open. The part next the baptistery is covered with a large semicylindrical vault, arched transversely to the “screen,” and penetrated by a less cylinder in the direction of the length of the loggia. Rebates (on baptistery side) round the doorway which stands between the pair of columns show that there was a door, and strips down the sides of the pillars, which stand above the transom, show that pierced slabs or other closures filled the arched front of the vault. If we add breast-high closures in the lateral openings, as in the portico of St. John Studius, the whole becomes an inclosed loggia against the baptistery. Salzenberg states that there was a door in the north wall of baptistery, and Labarte places another in the western compartment of south aisle of church, but for the latter there does not appear to be a particle of evidence; and consequently the court and loggia cannot have formed a direct passage to the baptistery. 1. Salzenberg on his plan draws the transverse axis of the baptistery, and that of the western bay of the church; these do not agree by a foot or two, but the doorway of “screen” agrees with neither, nor is it a mean between them, but varies by excess. 2. In the section (Salzenberg, Plate xi.) it is seen that the present level of floor in this loggia is that of baptistery, and is below that of church; but the columns have no bases, therefore the loggia floor was beneath both church and baptistery. 3. A large arch is shown between the church and west pier of this loggia, from which it springs properly, while at the other end it is cut off incomplete by the wall of the church. These reasons together lead us to suggest that the loggia is possibly older than the church, and that it may be a part of an arcade retained when the present church was built. The style of the screen would readily allow of its being twenty or thirty years older than S. Sophia. The capitals are not found elsewhere in the church, while similar ones form the chief order at S. Sergius; and the door is inserted between the two columns, exactly as in the portico of S. John Studius. We do not however insist on its being earlier than the church so much as on the evidence pointing to its being part of a continuous arcade (see plan, [Fig. 39]). Doubtless it might be determined from a careful examination whether the loggia or the baptistery was built first.
Fig. 39.—Restoration of Loggia by the Baptistery. Scale about eight feet to an inch.
The way by which the “Great Baptistery” was reached from the bema, as mentioned in the Ceremonies was probably by this cloister, which perhaps inclosed one of the courts on the sides of the church, spoken of by Procopius and the Silentiary. The portion drawn by Salzenberg still remains, although sadly plastered over and mutilated.