Carol Bartlett, age 15, of Hutchinson, Kan., for her question:

WHAT IS A FLYING BUTTRESS?

Buttress and flying buttress are terms used in architecture. A buttress is a pile of masonry built up against a wall to strengthen it, especially against lateral pressure, or thrust, from an arch or vault. As buttresses projected farther from the walls, flying buttresses were devised, consisting of a wall buttress and a parallel detached buttress connected to it by an arc.

Buttresses were used in ancient Mesopotamia and by the Romans, who built them against walls as piles of stone or against inside walls to serve as partitions. Vaulted romanesque cathedrals in early medieval Europe had buttresses in the form of shallow projecting piers.

Beginning in the 12th century, as Gothic cathedrals developed thinner walls and higher vaulted ceilings, withgreater lateral thrust, additional support was needed. And the flying buttress was developed.

The detached flying buttress was topped with a pinnacle or finial for added weight. Rows of carved pinnacled flying buttresses gave a delicate to such Gothic masterpieces as Notre Dame de Paris, Amiens and Beauvais.