The front on the street, east side, has a monumental entrance: a bay with an outer door, an inner doorway (Persian, dirkāh), a second door, and an inner īwān. The disposition is the same in the māristān. The entrance vault is not really a “clef pendante,” for the flat arch that supports it belongs to the original structure (1). This curious construction consists of a pair of cross vaults, appearing in the elevation as a pair of windows over the flat-pointed arch that bridges the bay and supports their middle. Without this arch, the springing point common to both would hang in the air. The construction is a conscious attempt to produce a “suspended” vault.
1. According to Allen, the "suspended keystone" was propped up with a later arch.
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Ernst Herzfeld. Damascus, Studies in Architecture I. Ars islamica v. 9, University of Michigan Press, 1942.
Ernst Herzfeld. Damascus, Studies in Architecture III. Ars Islamica XI-XII 1946 (p. 1-71).






