Lierne (vault)

A Lierne (from the French lier - to bind) in Gothic rib vaulting is an architectural term for a tertiary rib spanning between two other ribs, instead of from a springer, or to the central boss. The type of vault that utilizes liernes is called a lierne vault or stellar vault (named after the star shape generated by connecting liernes).

In England, the lierne came into use during the 14th century Decorated period. A good example of lierne vaulting is at Gloucester Cathedral. In France, examples can be seen in Flamboyant architecture, such as at Saint-Pierre, Caen.

The vault plan diagram of Ely Choir (right) shows the ribs as a double line, where the main longitudinal ridge rib (middle vertical lines) and transverse ridge ribs (alternate horizontal lines) intersect each other at the central bosses (large circles). The longitudinal ridge rib runs down the centre of the Choir, and the transverse ridge ribs span from the apex of each window at the sides of the Choir. Arched diagonal ribs span from piers between the windows, from springers to the central bosses, and arched transverse ribs (alternate horizontal lines) span from the springers to the main longitudinal ridge rib. Secondary arched diagonal ribs, called tiercerons, span from the springers to the transverse ridge ribs. Liernes (shaded black) span between the other ribs forming intricate patterning.

Note: In French terminology relating to architecture, a lierne is a ridge rib, and hence has a different meaning.

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