Here we are at the first floor (where the major mosaics are). Looking down we see in the left corner one of those huge vats from solid marble.
The six large disks with calligraphic inscriptions that adorn the central space at the height of the first floor, bear the names of Allah, Mohammad and the first four caliphs according to the Sunni tradition (Abu Bakr, Umar, Uthman and Ali). These calligraphies date from the 17th century (reign of Murat IV) and are the work of Hattat (= calligrapher) Teknicizade Ibrahim (died 1673).
Correspondent: J.M.Criel, Antwerpen.
Sources: ‘Türkiye Tarihi Yerler Kılavuzu’ – M.Orhan Bayrak, Inkılâp Kitabevi, Istanbul, 1994 .