Building around a dome

History, Our Neighbour

The Octroi post at Sirsi Circle and the Krishna Rao Pavilion both have uncommon, geometrical domes. Photos by Aravind C and Pankaj Modi

Two features tie together a police station, an octroi and a pavilion in Bengaluru. These disparate buildings are united by their unusual floor plans, which are neither square nor rectangular but have a central space that is surrounded by smaller rooms. Also rather unusual, these buildings are topped with polygonal domes.

Let’s begin with the police station in Basavanagudi, which was probably built in the early 1900s. It has a large circular hall which you enter through a front porch. Two rooms on either side open into the hall and there is also a back porch. Cinephiles might have seen this building in Kannada movies, many of which have scenes shot here.

Up next is the old Octroi post at the City Armed Reserve Quarters of the Bengaluru City Police. This building at Sirsi Circle was built sometime in the 1920s or early 1930s. The little structure has a small central space with three rooms branching off from it. Until recently, this octroi was abandoned and close to collapse, with a luxuriant tree growing through it. It was recently restored and now functions as a reading room.

The last of our set of three is the Krishna Rao Pavilion in the M N Krishna Rao Park in Basavanagudi. This two-storeyed structure was built in 1940-41, with a generous contribution from Sir M N Krishna Rao, a feted administrator in the Mysore government. The octagonal plan, the large dome, the porches and the curved staircases on its exterior mark the building as quite singular.

“Octagonal, hexagonal and circular buildings of this kind are quite different from the many public buildings we have, where the centre is emphasised by a dome,” says Pankaj Modi, conservation architect with INTACH. For example, these building forms are different from the Vidhana Soudha, Lalitha Mahal or Vani Vilas Hospital, all of which have prominent domes that serve to highlight the centre in a linear plan.

The polygonal domes on the three buildings are also uncommon. Most Islamic and Christian monuments have spherical, bulbous or onion domes. The exceptions are a few churches built during the medieval period in Europe. Closer home is Mysore’s Jayalakshmi Vilas Mansion which was built in 1905 and has a polygonal dome, one of the earliest we know of here.

What exactly is a polygonal dome? S Raghunath, a professor of civil engineering in BMS College of Engineering, Bengaluru, explains, “If you take a horizontal slice or section through a spherical dome, you will get a circle. In a polygonal dome, a horizontal section will give you the outline of a polygon.” A horizontal section through the octroi building’s dome, for example, gives a hexagon; in the Krishna Rao pavilion, a section gives an octagon.

Structural detail

According to Modi, another way of thinking of polygonal domes is to imagine the plane of the walls continuing upwards and then curving and narrowing to meet at a point to form the dome. “This is unlike the method of building a circular dome, which involves using squinches or pendentives to convert a square into an octagon and then a circle,” he says.

Raghunath points out another important structural detail. All domes are characterised by lateral thrust, a tendency for the base of the dome to push outward. This can be countered with buttresses or ring beams, both of which can be aesthetically unappealing. “In buildings like the octroi post, the walls and roofs of the rooms serve a structural purpose by countering the lateral thrust,” he says.

What prompted the construction of this clutch of buildings in this decidedly uncommon form? Were they inspired by English garden follies, those small decorative structures characterised by quirky architecture? In the 1800s, for instance, Thomas Metcalfe built two follies near Qutb Minar, one of which was a domed pavilion.

Or perhaps we should look to the last building in our list for some clues. The Krishna Rao pavilion was designed by the German architect Otto Koenigsberger but with inputs from Dewan Sir Mirza Ismail, who was partial to domes, axial symmetry and monumentality. Were the other two polygonal-domed buildings in Bengaluru also partly Sir Mirza’s influence? Perhaps, we shall never know.

Another thing that unites the police station, Octroi post and pavilion is that all three are in south Bengaluru, within walking distance from each other. Check them out the next time you are in the vicinity.

(Meera Iyer is the author of ‘Discovering Bengaluru’ and the Convenor of INTACH Bengaluru Chapter)