Chapter 14

BYZANTINE ARCHITECTURE.

BOOKS RECOMMENDED: As before, Essenwein, Hübsch, Von Quast. Also, Bayet, _L’Art Byzantin_. Choisy, _L’Art de bâtir chez les Byzantins_. Lethaby and Swainson, _Sancta Sophia_. Ongania, _La Basilica di San Marco_. Pulgher, _Anciennes Églises Byzantines de Constantinople_. Salzenberg, _Altchristliche Baudenkmäle von Constantinopel_. Texier and Pullan, _Byzantine Architecture_.

+ORIGIN AND CHARACTER.+ The decline and fall of Rome arrested the development of the basilican style in the West, as did the Arab conquest later in Syria. It was otherwise in the new Eastern capital founded by Constantine in the ancient Byzantium, which was rising in power and wealth while Rome lay in ruins. Situated at the strategic point of the natural highway of commerce between East and West, salubrious and enchantingly beautiful in its surroundings, the new capital grew rapidly from provincial insignificance to metropolitan importance. Its founder had embellished it with an extraordinary wealth of buildings, in which, owing to the scarcity of trained architects, quantity and cost doubtless outran quality. But at least the tameness of blindly followed precedent was avoided, and this departure from traditional tenets contributed undoubtedly to the originality of Byzantine architecture. A large part of the artisans employed in building were then, as now, from Asia Minor and the Ægean Islands, Greek in race if not in name. An Oriental taste for brilliant and harmonious color and for minute decoration spread over broad surfaces must have been stimulated by trade with the Far East and by constant contact with Oriental peoples, costumes, and arts. An Asiatic origin may also be assigned to the methods of vaulting employed, far more varied than the Roman, not only in form but also in materials and processes. From Roman architecture, however, the Byzantines borrowed the fundamental notion of their structural art; that, namely, of distributing the weights and strains of their vaulted structures upon isolated and massive points of support, strengthened by deep buttresses, internal or external, as the case might be. Roman, likewise, was the use of polished monolithic columns, and the incrustation of the piers and walls with panels of variegated marble, as well as the decoration of plastered surfaces by fresco and mosaic, and the use of _opus sectile_ and _opus Alexandrinum_ for the production of sumptuous marble pavements. In the first of these processes the color-figures of the pattern are formed each of a single piece of marble cut to the shape required; in the second the pattern is compounded of minute squares, triangles, and curved pieces of uniform size. Under these combined influences the artists of Constantinople wrought out new problems in construction and decoration, giving to all that they touched a new and striking character.

There is no absolute line of demarcation, chronological, geographical, or structural, between Early Christian and Byzantine architecture. But the former was especially characterized by the basilica with three or five aisles, and the use of wooden roofs even in its circular edifices; the vault and dome, though not unknown, being exceedingly rare. Byzantine architecture, on the other hand, rarely produced the simple three-aisled or five-aisled basilica, and nearly all its monuments were vaulted. The dome was especially frequent, and Byzantine architecture achieved its highest triumphs in the use of the _pendentive_, as the triangular spherical surfaces are called, by the aid of which a dome can be supported on the summits of four arches spanning the four sides of a square, as explained later. There is as little uniformity in the plans of Byzantine buildings as in the forms of the vaulting. A few types of church-plan, however, predominated locally in one or another centre; but the controlling feature of the style was the dome and the constructive system with which it was associated. The dome, it is true, had long been used by the Romans, but always on a circular plan, as in the Pantheon. It is also a fact that pendentives have been found in Syria and Asia Minor older than the oldest Byzantine examples. But the special feature characterizing the Byzantine dome on pendentives was its almost exclusive association with plans having piers and columns or aisles, with the dome as the central and dominant feature of the complex design (see plans, Figs. 74, 75, 78). Another strictly Byzantine practice was the piercing of the lower portion of the dome with windows forming a circle or crown, and the final development of this feature into a high drum.

+CONSTRUCTION.+ Still another divergence from Roman methods was in the substitution of brick and stone masonry for concrete. Brick was used for the mass as well as the facing of walls and piers, and for the vaulting in many buildings mainly built of stone. Stone was used either alone or in combination with brick, the latter appearing in bands of four or five courses at intervals of three or four feet. In later work a regular alternation of the two materials, course for course, was not uncommon. In piers intended to support unusually heavy loads the stone was very carefully cut and fitted, and sometimes tied and clamped with iron.

Vaults were built sometimes of brick, sometimes of cut stone; in a few cases even of earthenware jars fitting into each other, and laid up in a continuous contracting spiral from the base to the crown of a dome, as in San Vitale at Ravenna. Ingenious processes for building vaults without centrings were made use of--processes inherited from the drain-builders of ancient Assyria, and still in vogue in Armenia, Persia, and Asia Minor. The groined vault was common, but always approximated the form of a dome, by a longitudinal convexity upward in the intersecting vaults. The aisles of Hagia Sophia[17] display a remarkable variety of forms in the vaulting.

[Footnote 17: “St. Sophia,” the common name of this church, is a misnomer. It was not dedicated to a saint at all, but to the Divine Wisdom (Hagia Sophia), which name the Turks have retained in the softened form “Aya Sofia.”]

+DOMES.+ The dome, as we have seen, early became the most characteristic feature of Byzantine architecture; and especially the dome on pendentives. If a hemisphere be cut by five planes, four perpendicular to its base and bounding a square inscribed therein, and the fifth plane parallel to the base and tangent to the semicircular intersections made by the first four, there will remain of the original surface only four triangular spaces bounded by arcs of circles. These are called _pendentives_ (Fig. 71 a). When these are built up of masonry, each course forms a species of arch, by virtue of its convexity. At the crown of the four arches on which they rest, these courses meet and form a complete circle, perfectly stable and capable of sustaining any superstructure that does not by excessive weight disrupt the whole fabric by overthrowing the four arches which support it. Upon these pendentives, then, a new dome may be started of any desired curvature, or even a cylindrical drum to support a still loftier dome, as in the later churches (Fig. 71 b). This method of covering a square is simpler than the groined vault, having no sharp edges or intersections; it is at least as effective architecturally, by reason of its greater height in the centre; and is equally applicable to successive bays of an oblong, cruciform, and even columnar building. In the great cisterns at Constantinople vast areas are covered by rows of small domes supported on ranges of columns.

The earlier domes were commonly pierced with windows at the base, this apparent weakening of the vault being compensated for by strongly buttressing the piers between the windows, as in Hagia Sophia. Here forty windows form a crown of light at the spring of the dome, producing an effect almost as striking as that of the simple _oculus_ of the Pantheon, and celebrated by ancient writers in the most extravagant terms. In later and smaller churches a high drum was introduced beneath the dome, in order to secure, by means of longer windows, more light than could be obtained by merely piercing the diminutive domes.

Buttressing was well understood by the Byzantines, whose plans were skilfully devised to provide internal abutments, which were often continued above the roofs of the side-aisles to prop the main vaults, precisely as was done by the Romans in their thermæ and similar halls. But the Byzantines, while adhering less strictly than the Romans to traditional forms and processes, and displaying much more ready contrivance and special adaptation of means to ends, never worked out this pregnant structural principle to its logical conclusion as did the Gothic architects of Western Europe a few centuries later.

+DECORATION+. The exteriors of Byzantine buildings (except in some of the small churches of late date) were generally bare and lacking in beauty. The interiors, on the contrary, were richly decorated, color playing a much larger part than carving in the designs. Painting was resorted to only in the smaller buildings, the more durable and splendid medium of mosaic being usually preferred. This was, as a rule, confined to the vaults and to those portions of the wall-surfaces embraced by the vaults above their springing. The colors were brilliant, the background being usually of gold, though sometimes of blue or a delicate green. Biblical scenes, symbolic and allegorical figures and groups of saints adorned the larger areas, particularly the half-dome of the apse, as in the basilicas. The smaller vaults, the soffits of arches, borders of pictures, and other minor surfaces, received a more conventional decoration of crosses, monograms, and set patterns.

The walls throughout were sheathed with slabs of rare marble in panels so disposed that the veining should produce symmetrical figures. The panels were framed in billet-mouldings, derived perhaps from classic dentils; the billets or projections on one side the moulding coming opposite the spaces on the other. This seems to have been a purely Byzantine feature.

+CARVED DETAILS.+ Internally the different stories were marked by horizontal bands and cornices of white or inlaid marble richly carved. The arch-soffits, the archivolts or bands around the arches, and the spandrils between them were covered with minute and intricate incised carving. The motives used, though based on the acanthus and anthemion, were given a wholly new aspect. The relief was low and flat, the leaves sharp and crowded, and the effect rich and lacelike, rather than vigorous. It was, however, well adapted to the covering of large areas where general effect was more important than detail. Even the capitals were treated in the same spirit. The impost-block was almost universal, except where its use was rendered unnecessary by giving to the capital itself the massive pyramidal form required to receive properly the spring of the arch or vault. In such cases (more frequent in Constantinople than elsewhere) the surface of the capital was simply covered with incised carving of foliage, basketwork, monograms, etc.; rudimentary volutes in a few cases recalling classic traditions (Figs. 72, 73). The mouldings were weak and poorly executed, and the vigorous profiles of classic cornices were only remotely suggested by the characterless aggregations of mouldings which took their place.

+PLANS.+ The remains of Byzantine architecture are almost exclusively of churches and baptisteries, but the plans of these are exceedingly varied. The first radical departure from the basilica-type seems to have been the adoption of circular or polygonal plans, such as had usually served only for tombs and baptisteries. The Baptistery of St. John at Ravenna (early fifth century) is classed by many authorities as a Byzantine monument. In the early years of the sixth century the adoption of this model had become quite general, and with it the development of domical design began to advance. The church of +St. Sergius+ at Constantinople (Fig. 74), originally joined to a short basilica dedicated to St. Bacchus (afterward destroyed by the Turks), as in the double church at Kelat Seman, was built about 520; that of +San Vitale+ at Ravenna was begun a few years later; both are domical churches on an octagonal plan, with an exterior aisle. Semicircular niches--four in St. Sergius and eight in San Vitale--projecting into the aisle, enlarge somewhat the area of the central space and give variety to the internal effect. The origin of this characteristic feature may be traced to the eight niches of the Pantheon, through such intermediate examples as the temple of Minerva Medica at Rome. The true pendentive does not appear in these two churches. Timidly employed up to that time in small structures, it received a remarkable development in the magnificent church of +Hagia Sophia+, built by Anthemius of Tralles and Isodorus of Miletus, under Justinian, 532-538 A.D. In the plan of this marvellous edifice (Fig. 75) the dome rests upon four mighty arches bounding a square, into two of which open the half-domes of semicircular apses. These apses are penetrated and extended each by two smaller niches and a central arch, and the whole vast nave, measuring over 200 × 100 feet, is flanked by enormously wide aisles connecting at the front with a majestic narthex. Huge transverse buttresses, as in the Basilica of Constantine (with whose structural design this building shows striking affinities), divide the aisles each into three sections. The plan suggests that of St. Sergius cut in two, with a lofty dome on pendentives over a square plan inserted between the halves. Thus was secured a noble and unobstructed hall of unrivalled proportions and great beauty, covered by a combination of half-domes increasing in span and height as they lead up successively to the stupendous central vault, which rises 180 feet into the air and fitly crowns the whole. The imposing effect of this low-curved but loftily-poised dome, resting as it does upon a crown of windows, and so disposed that its summit is visible from every point of the nave (as may be easily seen from an examination of the section, Fig. 76), is not surpassed in any interior ever erected.

The two lateral arches under the dome are filled by clearstory walls pierced by twelve windows, and resting on arcades in two stories carried by magnificent columns taken from ancient ruins. These separate the nave from the side-aisles, which are in two stories forming galleries, and are vaulted with a remarkable variety of groined vaults. All the masses are disposed with studied reference to the resistance required by the many and complex thrusts exerted by the dome and other vaults. That the earthquakes of one thousand three hundred and fifty years have not destroyed the church is the best evidence of the sufficiency of these precautions.

Not less remarkable than the noble planning and construction of this church was the treatment of scale and decoration in its interior design. It was as conspicuously the masterpiece of Byzantine architecture as the Parthenon was of the classic Greek. With little external beauty, it is internally one of the most perfectly composed and beautifully decorated halls of worship ever erected. Instead of the simplicity of the Pantheon it displays the complexity of an organism of admirably related parts. The division of the interior height into two stories below the spring of the four arches, reduces the component parts of the design to moderate dimensions, so that the scale of the whole is more easily grasped and its vast size emphasized by the contrast. The walls are incrusted with precious marbles up to the spring of the vaulting; the capitals, spandrils, and soffits are richly and minutely carved with incised ornament, and all the vaults covered with splendid mosaics. Dimmed by the lapse of centuries and disfigured by the vandalism of the Moslems, this noble interior, by the harmony of its coloring and its impressive grandeur, is one of the masterpieces of all time (Fig. 77).

+LATER CHURCHES.+ After the sixth century no monuments were built at all rivalling in scale the creations of the former period. The later churches were, with few exceptions, relatively small and trivial. Neither the plan nor the general aspect of Hagia Sophia seems to have been imitated in these later works. The crown of dome-windows was replaced by a cylindrical drum under the dome, which was usually of insignificant size. The exterior was treated more decoratively than before, by means of bands and incrustations of colored marble, or alternations of stone and brick; and internally mosaic continued to be executed with great skill and of great beauty until the tenth century, when the art rapidly declined. These later churches, of which a number were spared by the Turks, are, therefore, generally pleasing and elegant rather than striking or imposing.

+FOREIGN MONUMENTS.+ The influence of Byzantine art was wide-spread, both in Europe and Asia. The leading city of civilization through the Dark Ages, Constantinople influenced Italy through her political and commercial relations with Ravenna, Genoa, and Venice. The church of +St. Mark+ in the latter city was one result of this influence (Figs. 78, 79). Begun in 1063 to replace an earlier church destroyed by fire, it received through several centuries additions not always Byzantine in character. Yet it was mainly the work of Byzantine builders, who copied most probably the church of the Apostles at Constantinople, built by Justinian. The picturesque but wholly unstructural use of columns in the entrance porches, the upper parts of the façade, the wooden cupolas over the five domes, and the pointed arches in the narthex, are deviations from Byzantine traditions dating in part from the later Middle Ages Nothing could well be conceived more irrational, from a structural point of view, than the accumulation of columns in the entrance-arches; but the total effect is so picturesque and so rich in color, that its architectural defects are easily overlooked. The external veneering of white and colored marble occurs rarely in the East, but became a favorite practice in Venice, where it continued in use for five hundred years. The interior of St. Mark’s, in some respects better preserved than that of Hagia Sophia, is especially fine in color, though not equal in scale and grandeur to the latter church. With its five domes it has less unity of effect than Hagia Sophia, but more of the charm of picturesqueness, and its less brilliant and simpler lighting enhances the impressiveness of its more modest dimensions.

In Russia and Greece the Byzantine style has continued to be the official style of the Greek Church. The Russian monuments are for the most part of a somewhat fantastic aspect, the Muscovite taste having introduced many innovations in the form of bulbous domes and other eccentric details. In Greece there are few large churches, and some of the most interesting, like the Cathedral at Athens, are almost toy-like in their diminutiveness. On +Mt. Athos+ (Hagion Oros) is an ancient monastery which still retains its Byzantine character and traditions. In Armenia (as at Ani, Etchmiadzin, etc.) are also interesting examples of late Armeno-Byzantine architecture, showing applications to exterior carved detail of elaborate interlaced ornament looking like a re-echo of Celtic MSS. illumination, itself, no doubt, originating in Byzantine traditions. But the greatest and most prolific offspring of Byzantine architecture appeared after the fall of Constantinople (1453) in the new mosque-architecture of the victorious Turks.

+MONUMENTS.+ CONSTANTINOPLE: St. Sergius, 520; Hagia Sophia, 532-538; Holy Apostles by Justinian (demolished); Holy Peace (St. Irene) originally by Constantine, rebuilt by Justinian, and again in 8th century by Leo the Isaurian; Hagia Theotokos, 12th century (?); Monétes Choras (“Kahiré Djami”), 10th century; Pantokrator; “Fetiyeh Djami.” Cisterns, especially the “Bin Bir Direk” (1,001 columns) and “Yere Batan Serai;” palaces, few vestiges except the great hall of the Blachernæ palace. SALONICA: Churches--of Divine Wisdom (“Aya Sofia”) St. Bardias, St. Elias. RAVENNA: San Vitale, 527-540. VENICE: St. Mark’s, 977-1071; “Fondaco dei Turchi,” now Civic Museum, 12th century. Other churches at Athens and Mt. Athos; at Misitra, Myra, Ancyra, Ephesus, etc.; in Armenia at Ani, Dighour, Etchmiadzin, Kouthais, Pitzounda, Usunlar, etc.; tombs at Ani, Varzhahan, etc.; in Russia at Kieff (St. Basil, Cathedral), Kostroma, Moscow (Assumption, St. Basil, Vasili Blaghennoi, etc.), Novgorod, Tchernigoff; at Kurtea Darghish in Wallachia, and many other places.