Musgum Tolek (Earthen Dome House)

The tolek is the traditional house of the Musgum (Mousgoum) people of Cameroon's Far North Region, notably around Maga in the Mayo-Danay division. It is a tall dome or cone in which wall and roof are a single shell of compressed, sun-dried mud, described in some accounts as laid over lashed reeds; there is no separate roof structure. French speakers called these houses cases obus, "shell houses", for their artillery-shell profile.

Form

Domes reach nearly 9 m (30 ft) in height. Their profile has been compared by architects to a catenary arch, the curve in which a self-supporting masonry shell carries its own weight in pure compression, which lets the walls be thick at the base and thin toward the top. Some are rounded beehives; others rise to an inverted-V point. A small round opening at the apex, a few centimetres across, ventilates the house, can be used as an escape hatch in floods and is closed with a slab or pot when it rains. The single door is keyhole-shaped, narrow at knee height and wider at the shoulders.

Construction

The tolek is built like a coiled pot. Mud mixed with water, sometimes with grass or other fibre, is laid in spiral rings about 0.5 m (20 in) high; each ring dries before the next is added. Few tools are needed. Instead of scaffolding, the raised geometric relief patterns on the outside give builders footholds during construction and later maintenance, and their V-shaped or straight grooves channel rainwater off the surface.

The compound

Several domes, together with granaries, are grouped around a central courtyard within a thatched enclosure wall; new dwellings could be added for new wives or daughters-in-law.

Decline and revival

With the arrival of cement and metal roofing, the tolek came to be seen as old-fashioned, and very few Musgum now build them; general surveys of African architecture describe them as no longer made. Renewed appreciation of their place in Musgum history has, however, led to some recent construction. The art historian Steven Nelson studied the form and its afterlife in From Cameroon to Paris: Mousgoum Architecture In and Out of Africa (2007), following an earlier article on the tolek in African Arts (2001).

Significance

The tolek is often cited as an example of how a vernacular builder can arrive at an efficient structural shape without calculation: a roof that is also a wall, built from the ground it stands on.