Fig. 26. Qasṭal. (From Provincia Arabia, by kind permission of Professor Brünnow.)
into a chapel, stood in the centre of the court;[203] in the barracks at Anderîn (A.D. 558) a chapel is similarly placed,[204] and at Qaṣr ibn Wardân (A.D. 561) a building, the uses of which have not been determined, stands in the barrack yard.[205] Beyond this small resemblance, the divergence of Qasṭal from the Roman camp type is complete. All the more noticeable is its likeness to the only Sasanian castrum of which we have any sufficient record. Qasṭal belongs to the same family as the fort at Qaṣr-i-Shîrîn ([Plate 73], Fig. 1). The towered walls, the single gate, the chambers or baits placed round the interior of the walls so as to leave a central court over, all these are characteristic of the older building; but at Qaṣr-i-Shîrîn the lodging of the commandant is placed inside the court, whereas at Qasṭal it is outside.[206] In the Zohâb district there is another building of a somewhat similar type, but it looks more like the ordinary caravanserai than like a fortress.[207]
The caravanserai type, when once it had established itself on the Arabian limes, was not to be ousted, but its later application is not only to fortress and barrack, but to genuine lodgings for caravans. In the Roman or Byzantine caravanserai of Khân al-Zebîb enough remains to show that the interior buildings were placed round the encompassing wall.[208] At Umm al-Walîd this interior arrangement is clearly preserved;[209] at Umm al-Rasâs baits, not unlike those of Qasṭal, are linked to the wall,[210] and the plan of a later building at Khân al-Zebîb (it is probably Moslem) differs not at all from that of a small modern caravanserai.[211] Khirbet al-Baiḍâ (see above, [p. 56]) belongs to the same group, but from its geographical position it must be regarded as a military station rather than as a true caravanserai, though it may have served both purposes. To what cause is the singularly rapid change from Roman camp to Asiatic caravanserai to be attributed? The answer is obvious. On the Arabian limes the builders were brought into contact with a strong Asiatic tradition; they were probably themselves local workmen, and they orientalized the Roman scheme. They applied from the first their own system of flanking towers to the defences; they grafted an injunctive plan on to the Roman camp plan, and they ended by discarding the latter in favour of the former.
The covering of dead ground by means of flanking towers and crémaillères goes back in western Asia to the earliest times. The plan of the acropolis of Gudea, drawn upon a tablet which is placed in the lap of a statue of the patesi of Lagash, exhibits, in the middle of the third millennium B.C., a system of fortification so fully developed that scarcely a dead angle exists in the whole circuit of the walls (Fig. 27). In the science of military engineering even Egypt would seem to have lagged behind Chaldaea, for the advantage of flanking towers was not understood there until the Asiatic expeditions of the Eighteenth Dynasty had taught the Pharaohs how to correct the defects in the unbroken lines of their massive defences.[212] In the Assyrian reliefs, double and triple rings of walls set thick with towers surround the towns; towered walls are represented in the ground-plans,[213] and excavation has proved the existence of rectangular towers in the walls of Khorsâbâd and of Assur.[214] A chemin de ronde, loopholes, and machicolations have been found in situ in the walls of Assur, together with traces of crenellation,[215] and all these features, as well as hourds projecting from the battlements, and the ladders and battering-rams which they were intended to counteract, are familiar upon Assyrian reliefs. Rounded towers have not been revealed by Babylonian or Assyrian excavations. They belonged to a later age or perhaps to a different sphere of culture, the Hittite or Syrian. But Dieulafoy observed them on the Achaemenid fortifications of Susa;[216] and at Hatra, while the inner walls of the town were flanked by rectangular towers, solid or casemated, and casemated bastions, on the outer wall a rounded tower has been recorded, and Dr. Andrae conjectures that it was one of many.[217] In this particular, as in the approximately circular outline assumed by its walls, Hatra may exhibit traits borrowed from the civilization of the southern Hittites. There are rounded and rectangular towers in the larger Parthian palace at Niffer.[218] In Sasanian fortifications the rounded tower seems practically to have displaced the rectangular.[219]
Fig. 27. Lagash. (From L’Acropole de Suse, by kind permission of M. Dieulafoy.)
Flanking towers strengthened the walls of Hittite cities. At Zindjirli the gradual development of more scientific methods can be traced in the successive walls which encompassed the town and the acropolis. The inner city wall, which was the first in date (it was probably built in the thirteenth century), is provided with rectangular towers which have a salience of 2 metres. The outer acropolis wall ([Fig. 5]), built about 900 B.C., has semicircular towers with a salience of 3½ metres; the strategic disadvantages of rectangular towers had been realized and corrected. A further improvement was effected in the inner cross wall, behind the main gate of the acropolis. The wall is built in retreating angles, and set with towers alternately rounded and rectangular; the rectangular towers project 1·80 metres from the face of the wall, while the rounded towers cover them with a projection of 4·50 metres. The outer city wall was built after the destruction of the city by Asarhaddon in 681 B.C. and is no more than a copy of the earliest wall, but at the same period casemates were added to the walls of the acropolis.[220] The Hittite capital of Qadesh on the Orontes, as depicted in the frescoes at Abû Simbel, a temple built by Rameses II (1388-1322), was protected by a wall with towers, the height of which must be due partly to the imagination of the Egyptian craftsman.[221] These towers have the appearance of being round, but the absence of architectural records of round towers at so early a date throws doubt upon the matter. In Asia Minor rectangular towers have been found upon the outer and the inner walls of Boghâz Keui;[222] they do not as a rule exceed a projection of 2½ metres. At Troy the earliest walls had towers 3 metres wide, and 2 metres salient; the curtain wall was in some places not longer than 10 metres, and the city gates were flanked by deep bastions. In the walls of the third period at Troy three towers were uncovered on the south-east side; they are 3·20 metres wide, 2·35 salient, and are separated from one another by a distance of only 6·40 metres.[223] But on the Greek mainland, at Tiryns, and at Mycenae, the fortifications are characterized by crémaillères and by deep bastions rather than by towers.[224] Much more lavish is the use of towers in the pre-Hellenic cities of Asia Minor, other than Troy. The very ancient acropolis on the Yamanlar Dâgh above Smyrna possessed rectangular towers.[225] In Caria the fortification known as the Wall of the Leleges opposite Iassos had rounded towers and crémaillères,[226] and the walls of Alinda rectangular towers à cheval.[227] The Lycian towns depicted upon the bas-reliefs in the tombs at Pinara, discovered by Benndorf and Niemann, exhibit salient rectangular towers,[228] while fortified towers of the same character are depicted on the monument of the Nereids at Xanthos,[229] and we have a plan of the ancient walled town of Pydnai in which the features portrayed on the reliefs are clearly to be recognized.[230] Nor must the towns of the Phoenicians be forgotten, the towered walls of Mount Eryx in Sicily, of the acropolis of Lixos in Mauritania Tingitana, of Thapsus, of Carthage, and of Tyre.[231]