Subsequently, Abdál Sinán, when Mi’már Báshí, added some embellishments to this mosque, and, at a later period, ’Alí Kúshjí, the celebrated astronomer, erected a school for the instruction of Muselmán children in the Korán within the precincts (harem) of this mosque, near the Dyer’s gate (Bóyájíler kapú-sí) opposite to the great dome. The same astronomer also placed there a sun-dial, which has not its equal in the whole world. It is engraved on a square marble tablet, according to that text of the Korán:—“Dost thou at all know how thy Lord hath extended the shadow?” After these events, in the reign of Báyazíd Velí, there was a great earthquake at Islámból for seven days and six nights. The castle of Ghalatah was damaged in many places; but it was repaired by the architect, Murád, who recorded the date of the repairs in an inscription engraved in the Jellí character on a square marble tablet. The reparations of the city were finished in sixty days. It is written, that this was the severest earthquake since the time of Yánkó ibn Mádyán. Báyazíd afterwards built a bridge of fourteen arches over the river Sakariyah, at the town of Keïveh, in the Sanják of Izmít (Nicomedia); another of nineteen arches, over the river Kizil Irmák, at the city of ’Osmánjik; and a third of nineteen arches, over the Gedúz (Hermus), in the province of Sárú khán; after which he began to build the mosque that bears his name, near the old palace in Islámból. Its foundations were laid in the year 903 (A.D. 1498), and it was finished in A.H. 911 (1505-6). It is built nearly in the same style as the mosque of his father Mohammed the Conqueror; but its two minarets are contiguous, not to it, but to the two rows of houses built on each side for the accommodation of strangers, which were subsequently added to the mosque. _Description of the Mosque of Sultán Báyazíd II._