This is the first voussoir at the springing level on either side of an arch and it is immediately adjacent to the skewback.
🏛️ Deconstructing the Arch: The Starting Point
This question asks you to identify the specific name for the first stone that begins the curve of an arch from its support.
(D) Springer: The First Stone of the Curve
The Springer is the correct answer. It is the lowest voussoir (wedge-shaped stone) on each side of the arch. Its name comes from the fact that it is the point from which the arch "springs" upwards from its support. It is located at the springing level and rests directly on the angled surface of the support, known as the skewback.
(A) Key: The Final Stone
The Key or Keystone is the final, central voussoir placed at the very top (apex or crown) of the arch. It is the last stone, not the first.
(B) Crown: The Highest Point
The Crown is the highest part or area of the arch. While the keystone is located at the crown, the crown itself is a location, not a specific stone.
(C) Abutment: The End Support
The Abutment is the entire structural support at the end of an arch. It takes the full load and horizontal thrust from the arch and transfers it to the foundation. The springer rests on the abutment, but it is not the abutment itself.
🖼️ Visual Diagram of Arch Components
This diagram clearly illustrates the location of the Springer as the first stone of the arch, resting on the abutment at the springing line.
🧱 The Importance of Voussoirs
It's important to remember that a Springer is a specific type of voussoir.
- Voussoir: The general term for any wedge-shaped unit that forms the courses of an arch.
- Springer: The specific name for the first voussoir at the bottom of the curve.
- Keystone: The specific name for the final voussoir at the top of the curve.