on the squinch

a squinch is a small arch, niche or load-bearing structure which joins a dome to a square base.

Its etymology is unclear but it may have something to do with scunch, a shortening of the Middle English sconcheon from the Old French escoinson, meaning angle or corner.

The earliest examples of squinches are found in ancient Persian architecture, built during the Sassanid Empire just under two thousand years ago. They are hefty and purposeful and seem to hold up an entire roof in one shadowy corner of curving brickwork.

The drawings of squinches — here, and in the magazine — are by the architect Nabil Haque.