Tuesday, June 30, 2020 –
Today we are going to get extremely technical and discuss the Gothic arch. Not to brag, but Gothic architecture has some pretty sweet physics at play in their doorways and ceilings. Sure, arches and vaulted ceilings have been around for ages, but now we have points! Sharp angels! Sweeping heights!
Gravity ain’t got nuttin’ on these bad boys! The math on this stuff is, like, WHHAAAT!? (Insert little mind blown emoji). Okay, so I won’t be going into the math. You can relax. I will be talking about the general terms for different sections of the arch.
Gothic Arch: unlike the rounded Roman arch, the Gothic arch has a sharp, pointed top.
Keystone: it still has a keystone at the top to hold everything in place. Sometimes there are two stones at the top, joined together, acting as the keystone.
Extrados: the upper or outer curve of an arch.
Intrados: the lower or inner curve of an arch.
Archivolt: a band of molding around the lower curve of an arch.
Voussoir: a wedge-shaped or tapered stone used to construct an arch.
Impost: a projecting block resting on top of a column, or sometimes embedded in a wall. It serves as the base for the springer or lowest voussoir of an arch. It is where the weight of the arch rests.
Soffit: the underside of a structure, like an arch or lintel.
Springer: the lowest stone in an arch. It is where the curve begins.
Springline: this is the point or line at which an arch or vault begins to curve.
Rise: this is the vertical distance between the spring line of an arch or vault and the bottom of the keystone (i.e. the height of the arch).
Span: the horizontal distance between the two supporting members (columns) of an arch (i.e. the width of the arch).
Column: that tall, skinny thing under the arch.
Engaged Column: a column that is attached (embedded in) to a wall.
Abacus: a projecting block on top of a column’s capital. It does not hold up an arch. Sometimes in Gothic architecture the abacus and impost block serve the same function, in which case it is called an impost.
Capital: the top part of a column. It is usually larger and somewhat ornate.
Shaft / Barrel: the main part of the column. It can be smooth, ribbed, fancy, not fancy…you name it!
Base: the very bottom part of the column. It is usually wider in order to support the weight of the column.
Spandrel: the triangular-ish space between the outermost curves of two arches, or an arch and a wall, and the ceiling above.
Tympanum: the triangular-ish space between the innermost curves of an arch and the lintel below.
Lintel: a horizontal support across the top of a door or window.
Whew! That was a lot! But, now you can have pointless conversations about the nitty-gritty parts of a Gothic arch. You’re welcome!
Tomorrow is July 1st. I will be taking a short break from architecture in order to give you a handout on the Most Precious Blood of our Lord, Jesus Christ.
Heart of Jesus, abyss of all virtues, have mercy on us!