Build the tower for the call to prayer in the form of the regional tradition: square and stepped in the Maghreb and Spain, cylindrical and tapering in Iran and Central Asia, needle-like and polygonal in the Ottoman lands.
Rules · Domes · Structure · Façades
The bulbous double dome
Cover the tomb chamber with a low inner dome and raise over it, on a tall drum, a bulbous outer shell whose swelling profile is visible from every direction.
The Mughals inherited the double dome from Timurid Central Asia. At Humayun’s Tomb the outer dome is a white marble hemisphere; at the Taj it becomes an onion that swells beyond the drum before closing in a reverse curve to the lotus crown and finial. Inside, the octagonal cenotaph chamber is covered by a much lower dome, and between the two shells lies a tall void never seen by visitors. The outer shell exists for the view across the garden and the river.
Related rules
Set the iwan arch in a tall rectangular screen that rises above the roofline, framed by bands of inscription and flanked by minarets.
Build two domes, one above the other: an inner shell proportioned to the room below and an outer shell raised on a tall drum and proportioned to the city outside.
outer crown ≫ inner crown; the gap may be a third of the total height
Balance the tomb so that the dome with its finial rises as high above the pishtaq as the pishtaq rises above the plinth, and let every element be answered by its mirror image on both axes.
pishtaq ≈ dome + finial ≈ 33–35 m; total ≈ 73 m (approximate)
Mark the corners of roofs, minarets and gateways with chhatris: small open domed kiosks on columns with a projecting eave.
Stand the minarets free at the corners of the plinth, so that they frame the tomb in every view without crowding it.
Cite this page Chris Paton, “The bulbous double dome”, The Textbook of Architecture, https://textbookofarchitecture.com/rule/mughal-double-dome. Text, drawings and models licensed under CC BY-NC 4.0.