Looking at Buildings

GeometricGlossary Term [1]' is a termGlossary Term [2] used for the early type of bar traceryGlossary Term [3], a French invention adopted for the East end of Westminster Abbey, begun in 1245. The chapel windows, seen to the left, are divided into two lights separated by a slim central mullionGlossary Term [4] with a pointed archGlossary Term [5] above filled by a foiled circle.

• See how simple bar traceryGlossary Term [6] is formed

The principal of the window with several lights surmounted by a circle could be elaborated for larger areas, by increasing the number of lights and circles. Large C13 windows of the GeometricGlossary Term [7] period had an even number of lights arranged in pairs, each pair with its own circle. See how a complex GeometricGlossary Term [8] window is composedThe largest example is the eight-lightGlossary Term [9] east window of Lincoln Cathedral Angel ChoirGlossary Term [10] where the window is made up of two times two pairs, or 4 + 4 lights, with a total of 13 circles of different sizes in the window head.