The historian alludes to that work when describing the site upon which the Crusaders established their camp in 1203, and from his account of the matter there can be no doubt regarding the portion intended. The Latin camp, says Nicetas,[467] was pitched on the hill which faced the western front of the Palace of Blachernæ, and which was separated from the city walls by a strip of level ground, extending from the Golden Horn, on the north, to the wall built by the Emperor Manuel, on the south. This is an unmistakable description of the hill which stands to the west of the fortifications between the Golden Horn and Egri Kapou, and which is separated from those fortifications by a narrow plain, as by a trench or gorge. Consequently, the wall erected by the Emperor Manuel must be sought at the plain’s southern extremity; and there, precisely, commences a line of wall which displays, as far as the north-western corner of the court of the Palace of the Porphyrogenitus, a style of workmanship perfectly distinct from any found elsewhere in the bulwarks of the city. The object of building this wall was to add to the security of the Palace of Blachernæ, which became the favourite residence of the Imperial Court in the reign of Alexius Comnenus,[468] and which Manuel himself enlarged and beautified.[469] The new wall was not only stronger than the earlier defences of the palace, but had also the advantage of removing the point of attack against this part of the city to a greater distance from the Imperial residence. At the same time, the older fortifications were allowed to remain as a second line of defence. In construction the wall is a series of lofty arches closed on the outer face, and built of larger blocks of stone[470] than those generally employed in the Walls of Theodosius. On account of the steepness of the slope on which it, for the most part, stands, it was unprotected by a moat, but to compensate for this lack the wall was more massive, and flanked by stronger towers than other portions of the fortifications. At the summit the wall measured fifteen feet in thickness. Of its nine towers, the first six, commencing from the court of the Palace of the Porphyrogenitus, are alternately round and octagonal; the seventh and eighth are octagonal; the last is square. The wall was provided with a public gate and, apparently, two posterns. One postern, opening on the Theodosian parateicheion, was in the curtain[471] extending from the outer wall of the court of the Palace of the Porphyrogenitus to the first tower of Manuel’s Wall. The other postern stood between the second and third towers, and is remarkable for being the only entrance in the city walls furnished with a drip-stone. Dr. Paspates[472] identified it with the Paraportion of St. Kallinikus; but the postern of that name is mentioned in history before the erection of Manuel’s Wall.