A lancet arch is a pointed arch that is markedly taller than it is wide, with the centres of its two component arcs lying outside the span of the arch. That makes it rise narrow and steep, like the point of a lancet. It is the signature of the early Gothic — in England the Early English period, roughly 1180 to 1250.
How the shape is set out
A pointed arch is drawn from two arcs meeting at the apex. Where the centres of those arcs sit determines the form:
- Centres inside the span — the arch becomes wider and flatter: the drop arch.
- Centres at the springing points themselves — the equilateral arch, where the radius equals the span.
- Centres outside the span — the lancet arch: narrow, tall and steep.
The structural advantage
An arch pushes not only downwards but outwards. That horizontal thrust has to be taken by the supports. The steeper the arch, the smaller the thrust for the same load. This is precisely why Gothic builders working in pointed arches could go higher and slenderer than the Romanesque round arch allowed: less thrust means narrower piers and less massive abutment. What thrust remains is carried away outside the building by buttresses and flying buttresses.
Application
The lancet arch is used over windows, in blind niches, in arcades and over doorways. Salisbury Cathedral is the textbook example, with long ranges of narrow lancets. Elsewhere the form reappears above all in the nineteenth-century Gothic Revival, which deliberately took up the early Gothic vocabulary.
Points to watch in masonry: the steep arch calls for sharply tapering voussoirs or carefully formed wedge joints. In restoration, the masonry cracks first at the springing, because the support has drifted outward over the centuries — look there before you look at the crown.
Related terms
- Lancet window
- Arch
- Drop arch
- Ogee arch
- Gothic
- Buttress
- Flying buttress
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