The dome of the southwest corner room, which is one of the four rooms forming the ‘zaviye’ (dervish lodge) or ‘misafirhane’ (guest house).
This inner dome does not correspond to an outside one; on the contrary: the outer roof is flat. Consequently, only two of the eight windows under the dome are real windows that let the light in; they are located in the corner walls of the building. The other six ‘windows’ are ornamental, and create the (false) impression that the dome rests on a drum.
The (recently refreshed) painted decoration of the dome is called ‘kalem işi’ (= work of the pen/paintbrush), because it is inspired on the geometric or stylised ornamentation used by Ottoman calligraphers to illuminate books. It displays the 19th century late-Ottoman ‘Turkish Baroque’ style, which was influenced by European Neo-Classicism and Neo-Barok. The paintings on the maqarnas-shaped ornaments in the corners are slightly older: they date from the 18th century.

Correspondent: J.M.Criel, Antwerpen.
Sources: ‘Vakıf Abideler ve eski Eserler’ - Vakıflar Genel Müdürlüğü III, Ankara 1983
& "Architecture ottomane. Ouvrage autorisé par irade impérial et publié sous le patronage de son excellence Edhem Pacha pour l'exposition universelle de 1873", published 1873 .