But however interesting the old churches of the city are as historical landmarks, however useful as a clue to guide us through the labyrinth of the life of New Rome, their supreme value after all consists in the fact that they are monuments, one of them the finest monument, of what is styled Byzantine Art—the art which blended artistic elements derived from Greece and Rome with artistic elements borrowed from Nineveh, Persia, Syria, and unfolded a new type of beauty. It was the flower developed by that fusion of Western and Oriental æsthetic ideals and tastes resulting from the long intercourse maintained between Europe and Asia, sometimes at the point of the sword, and sometimes by the peaceful ministries of commerce. Nowhere could that Art find a more congenial atmosphere in which to flourish than in the city which binds the West and the East together. Like all else in the world, Byzantine Art was not a sudden creation, independent of all antecedents, unheralded by previous analogous forms. The dome was reflected in the waters of the Tigris and of the Tiber before it was mirrored in the Bosporus. Columns were bound together by arches instead of by a horizontal entablature, in the Palace of Diocletian at Spalato, before they were so united in the Sacred Palace beside the Hippodrome of Constantinople. Walls glistening with variegated marbles, marble floors glowing with colours that vied with meadows in flower, mosaics radiant with the hues of the rainbow, had adorned homes and made palaces beautiful before the witchery of such coloration cast a spell over the courtiers of Justinian, or suffused the light in S. Sophia. Even the pendentive that fills the triangular space between two contiguous arches at right angles to each other, so characteristic of Byzantine architecture, is claimed to be an earlier device in domical construction. Be it so. In one sense, there is nothing new under the sun. The new grows out of the old, the present is the product of the past. And yet, while a new order of things must spring from an old order, it is not the bare repetition of what has been; while it must employ materials shaped originally for the use of other days, it is not the mechanical combination of those materials. It employs them in another spirit, under the control of ideas different or more mature than have yet been known, as the utterance of feelings acting with peculiar force at particular moments in history, with more skill, on a larger scale, with happier effect, and the result is that something appears with an individual entity perfectly distinguishable from all that ever was before, or that will ever come after. Byzantine Art is its own very self, however many adumbrations prophesied its advent.
The oldest ecclesiastical edifice in the city—the Church of S. John the Baptist, attached to the monastery of Studius—does not, however, represent Byzantine architecture. Built in 463, it is a basilica, and accordingly is a specimen—the only specimen in Constantinople—of the earliest type of a Christian sanctuary. It was well-nigh destroyed in a conflagration that devastated the district of Psamatia in 1782, and its roof was crushed in by a heavy fall of snow some three winters ago. But, though only the shadow of its former self, its primitive character can be clearly recognised. The old atrium before the church is still here, with a phiale or fountain in its centre for the purification of the gathering worshippers. Of the colonnaded cloister along the four sides of the atrium, the western portion, borne by four columns and forming the narthex of the church, still stands. There catechumens and penitents, unworthy to tread the holy ground within the sanctuary, stood outside and afar off. Beautiful trees now spread their branches over the court, and the shaded light falls upon turbaned Moslem tombs, as of yore it fell upon the graves of Christian monks, from the trees growing in the Paradise of the monastery. It is the most peaceful spot in all Constantinople, and as fair as it is calm and quiet. The narthex belongs, undoubtedly, to the original fabric. Its marble pillars crowned by Corinthian capitals of a late type bear a horizontal entablature, and the egg and dart ornament, the dentils, the strings of pearls, familiar in the friezes of Greek and Roman temples mingle with foliage, birds, and crosses, expressive of new ideas and tastes. Within, the interior was a hall 89 feet by 83, divided by a double row of seven columns of verde antique marble, into a nave and two aisles. The proportion of length to breadth is greater than is usual in basilicas of the West, and an indication of the tendency to assume the square plan which Byzantine architecture so strongly manifests. The long lessening vistas so impressive in Western churches are rarely, if ever, found in an Eastern sanctuary. In the latter the structure is more compact, and the worshipper stands before a Presence that compasses him about alike on every side. At the eastern end of the nave is the usual apse, semicircular within, a polygon of three sides on the exterior. Triforium galleries, now gone, divided the aisles in two stories, the upper storey bearing also columns of verde antique. The columns of the lower tier were bound by a horizontal entablature, while their fellows above were united by arches, a mingling of old and new forms. The roof was of wood, as in similar basilicas elsewhere. The church recalls the Church of S. Agnes at Rome. Its disappearance will be a matter of deep regret, not only as an ancient landmark, but as an edifice which preserved the surroundings of early Christian congregations, and reflected, however faintly, the light of classic days, through all the changes of the city’s tastes and fortunes.
The Church of S. Irene, notwithstanding the serious restorations it underwent in the sixth century and again in the eighth, retains so much of its early basilican type that it can claim a place among the churches of the older style. In spite of the two domes placed longitudinally upon its roof, it is basilican in the proportion of its length to its breadth, in the retention of lines of piers and columns to divide its nave and aisles, in its single apse, and the galleries on three sides. The apse has the interest of still preserving the tiers of marble seats for the clergy, as in the Cathedral of Torcello. Its conch is adorned with the mosaic of a large black cross on gold ground, and on the face of the triumphal arch may be read the invocation calling upon the Hope of all on the earth or upon the sea to enter His temple, and pour His Spirit upon His people.
SS. Sergius and Bacchus, styled by the Turks little S. Sophia (Kutchuk Aya Sofia), on account of the resemblance it bears to the greater church of that name, is interesting from more than one point of view. It deserves attention as a thing of beauty. Imagine an octagonal building constructed of eight lofty piers united by arches. Cover that structure with a dome furrowed by sixteen flutings. Let the sides in the diagonals be curved and the sides in the axes be straight, to secure more room, to avoid monotony of contour, stiffness, angularity, and to introduce the variety, freedom, softness, which give wings to fancy. Within each archway, except the one at the east, where the semicircular apse recedes to make room for the altar and the seats of the clergy, place four columns in two tiers, now green mottled with black spots, now cream-coloured marked with red veins, now white marked with veins of dark blue. Crown the lower columns with capitals, whose lobed form has been compared to a melon partly cut open, but which might, more gracefully, be likened to a tulip bud breaking into flower. Bind these columns, after the old fashion, with a horizontal entablature, where acanthus, egg and dart, reeds and reel, dentils, strands of rope and the ornamental letters of an inscription, in honour of S. Sergius and of the founders of the church, Justinian and Theodora, combine to make a splendid frieze. Join the upper columns, according to the new taste, with arches supporting conchs, and resting on long, flattened capitals covered with marble lace. Revet all surfaces up to the cornice with variegated marbles, and above the cornice spread mosaics. Then put this octagonal fabric, with its undulated interior surface, thus carved and coloured and gemmed, into a square edifice, like a jewel into a casket; so that the apse may protrude beyond the square’s eastern side, and the aisle, between the octagon and the square, may be divided into two stories by galleries, and the round dome may soar aloft visible to all without, and you have some idea of the plan and beauty of this gem of Art.
Another consideration that lends interest to SS. Sergius and Bacchus is its striking resemblance to the Church of S. Vitale at Ravenna. The latter was commenced in 526, a year earlier than the former, while Theodoric the Great ruled his Ostrogoths in the fair city beside the Adriatic. It was not completed, however, until 547, after the arms of Justinian had restored Ravenna to the Roman Empire. A comparison between the kindred buildings would be invidious. Let it suffice to say, speaking broadly, that the exterior arrangements of SS. Sergius and Bacchus are superior to those of its western companion, while the interior of S. Vitale is more beautiful than the interior of the church on the shore of the Sea of Marmora. But, leaving comparisons between two beautiful objects alone, it is pertinent to recognise the artistic influence of Constantinople over Art in the West here manifested. For, although the churches are too different for the one to have been copied from the other, they are so similar as to prove the existence of a common school of Art; a school which had its chief seat in the studios and workshops beside the Bosporus. Even some of the materials of S. Vitale were imported from the East; among them, “melon-capitals” like those which adorn the columns on the ground-floor of SS. Sergius and Bacchus.
The similarity of the two churches has yet another interest. Their likeness constitutes them symbols of Justinian’s great policy—the reunion of the East and the West, a reunion maintained for some two hundred years after its consummation. Since that unity was impaired, they have stood, one beside the Adriatic, the other beside the Marmora, like hills which erewhile formed sides of the same mountain, and rose to the same peak, but which a cruel tide has torn apart and holds separate, in spite of their kinship.
But, perhaps, the chief interest attaching to SS. Sergius and Bacchus is the fact that it represents a stage in the solution of the problem how to crown a square building with a dome, the characteristic mark of Byzantine architecture.
To cover a round building, round from summit to base like the Pantheon, with a dome is comparatively an easy matter, for in that case two circular structures meet and fit together along the whole circuit of their circumferences. On the other hand, to set the round rim of a dome upon a square substructure seems an attempt to join figures which from the nature of things can never coalesce.
Such a union is conceivable, only if, by some device, the different figures can, at least at some point, be cut to the same shape. The problem to be solved may therefore be stated as the question, whether the summit of a square structure can be converted into a circle corresponding to the rim of the dome it is to support. In SS. Sergius and Bacchus we have the type of a building in which a step was taken in that direction. There, as we have seen, the base upon which the dome rests is formed by a substructure consisting of eight arches arranged in the figure of an octagon; the gaps at the angles, where arch bends away from arch, being filled with masonry to the level of the heads of the arches. Such a base, it is true, does not match the dome as accurately as a round substructure like the Pantheon. Still, an octagon approximates to a circle more closely than a square does. Its contour offers more points of contact to the orbed canopy set upon it, and the gaps at its angles, being comparatively small, can readily be filled up to afford the dome a continuous support. If the fit is not perfect, it is sufficient to secure a decided advance beyond the simpler art, which knew only how to put one round thing upon another round thing. And what beautiful results could be gained by this advance, SS. Sergius and Bacchus in Constantinople and San Vitale at Ravenna are there to prove. But the end was not thus reached. Circular buildings and octagonal buildings are exceedingly beautiful; they should always stay with us. But they are not the most convenient, and cannot become the buildings in general use. For the practical purposes of life, square or oblong halls are in greater demand; such as the basilica, which could serve as a court of justice, a church, a school, a market, or a throne-room. Hence the question still remained, Can the summit of a square structure be turned into a circular base for a dome?
And it is the merit of the architects of S. Sophia, Anthemius of Tralles and Isidorus of Miletus, his nephew, to have applied the method which solves that problem, with such ability, such splendid success, and to have made it so conspicuous and famous, that they seem the discoverers of the method, and not only its most illustrious exponents. The object which these men set themselves to accomplish was to combine the advantages of a basilican edifice with the advantages of a domical building. For, in S. Sophia, the lineaments and beauty of a basilica are still retained—the threefold division of a stately hall into nave and aisles, the recess of the apse at the east end, the galleries dividing the other sides into two stories, long lines of columns, the lustre of marble and the glow of mosaics all are here. But the ceiling of a basilica, whether flat, pointed, or vaulted, was an insignificant feature. It cramped the upward view; it vexed the eye as heavy. In a church, it seemed to fling back to earth the aspirations which sought the heavens. It was dark; through it the Light of the world could not stream into the soul.