Outside of the exterior wall he built a third, the height of which, measured from the bottom of the ditch, is twenty-five cubits, and its breadth six cubits; the distance between this and the middle wall being forty cubits: and beyond the third wall there is a ditch one hundred cubits broad, into which the sea formerly passed from the Seven Towers as far as the gate of Silivrí; and being admitted on the other side from the gate of Iyyúb Ansárí to the Crooked gate (Egrí-kapú), the town was insulated. This triple row of walls still exists, and is strengthened by 1225 towers, on each of which ten watchful monks were stationed to keep watch, day and night. The form of Islámbúl is triangular, having the land on its western side, and being girt by the sea on the east and north, but guarded there also by a single embattled wall, as strong as the rampart of Gog and Magog. Constantine having, by his knowledge of astrology, foreseen the rise and ascendancy of the Prophet, and dreading the conquest of his city by some all-conquering apostle of the true faith, laid the foundation of these walls under the sign of Cancer, and thus gave rise to the incessant mutinies by which its tranquillity has been disturbed. It is eighteen miles in circuit; and at one of its angles are the Seven Towers pointing to the Kiblah (Meccah). The Seraglio-point (Seráï-búruní) forms its northern, and the gate of Iyyúb its third and north-western angle. Constantine having taking to wife a daughter of the Genoese king (Jenúz Králí), allowed him to build some strong fortifications on the northern side of the harbour, which were called Ghalatah, from the Greek word _ghalah_ (γάλα, milk), because Constantine’s cow-houses and dairy were situated there. _Names of Constantinople in different Tongues._