A lierne is a vault rib that neither springs from the vault’s springing point nor runs to the central boss, but instead links two other ribs together. It is an intermediate rib that thickens the rib pattern of a Gothic vault into a net.
That sets it apart from the two rib types that do start at the springing: the diagonal rib (the main rib of a rib vault) and the tierceron (an extra rib running from the springing to a point on the ridge rib).
Where the lierne comes from
The early Gothic rib vault had only diagonal ribs, transverse ribs and wall ribs. From the thirteenth century that pattern was progressively refined: first with tiercerons, then with liernes linking tiercerons and diagonal ribs to each other. This produced the net vaults and star vaults characteristic of the late Gothic — in the Low Countries mainly in the fifteenth and sixteenth centuries.
At the intersection of liernes and other ribs there is often a small boss, sometimes carved with a coat of arms, a flower or a head. In a richly worked star vault you can count dozens of bosses this way.
Structural or decorative?
In the early Gothic the rib was a structural member: the vault was built up on the ribs and the ribs carried the vault cells. The lierne, however, usually sits above a part of the vault surface that the main ribs already carry. In many cases it is therefore chiefly formal: it divides the vault surface into smaller, more manageable cells and enriches the pattern.
That does not make the lierne unimportant. Smaller cells are easier to build, need lighter centering, and distribute loads more evenly across the vault.
How to spot one
Stand under the vault and follow the ribs with your eyes from a pier:
- Does the rib run diagonally from the springing to the middle of the bay? That is a diagonal rib.
- Does it run from the springing to a point on the ridge, but not to the centre? That is a tierceron.
- Does the rib not touch the springing at all, and link two other ribs instead? Then you are looking at a lierne.
Related terms
- Vault rib
- Rib vault
- Net vault
- Star vault
- Boss
- Transverse arch
- Gothic
- Vault
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