Tracery
Tracery is an architectural device by which windows (or screens, panels, and vaults) are divided into sections of various proportions by stone bars or ribs of moulding.
The purpose of the device is practical as well as decorative, because the increasingly large windows of Gothic buildings needed maximum support against the wind.
[2] The term probably derives from the tracing floors on which the complex patterns of windows were laid out in late Gothic architecture.
[3] The evolving style from Romanesque to Gothic architecture and changing features, such as the thinning of lateral walls and enlarging of windows, led to the innovation of tracery.
However, instead of a slab, the windows were defined by moulded stone mullions, which were lighter and allowed for more openings and intricate designs.
From around the 1140s, the pointed arch Gothic window (employed by Abbot Suger for the redesign of the choir at St Denis) started to take over.
As the buttressing systems of early Gothic architecture reduced the structural need for broad expanses of thick walls, window openings grew progressively larger and instead of having just one very large window per bay division (which would create problems with supporting the glass), the typical early-Gothic 'twin lancet plus oculus' form of plate tracery developed.
This greatly limited the overall amount of light admitted to the interior by these windows, as well as restricting the complexity of patterns that could be created.
[1] Bar tracery, an important decorative element of Gothic styles, appeared first at Reims and was employed in England around 1240.
1350) was enabled by the development of bar tracery in Continental Europe and is named for the radiation of lights around a central point in circular rose windows.
The Reims windows still used the same 'two lancets plus oculus' pattern (as in the Soissons example above), but now the glass panels were held between narrow stone mullions made up of carefully shaped lengths of masonry (fitted together with mortar and metal pins) quite distinct from the wall surrounding them.
These mullions were much more slender than the corresponding elements in plate-tracery windows and crucially, the previously solid wall areas such as the spandrels could also now be glazed, greatly increasing the amount of light admitted.
The use of the ogee in curvilinear tracery can be seen in the west window of St Mary's parish church in Cottingham, East Riding of Yorkshire.
Reticulated tracery fills the head of the arch with repeated forms creating the appearance of a net-like pattern.
[8] Third Pointed or Perpendicular Gothic developed in England from the later 14th century and is typified by Rectilinear tracery (panel-tracery).
[1] Perpendicular strove for verticality and dispensed with the Curvilinear style's sinuous lines in favour of unbroken straight mullions from top to bottom, transected by horizontal transoms and bars.
[2] Four-centred arches were used in the 15th and 16th centuries to create windows of increasing size with flatter window-heads, often filling the entire wall of the bay between each buttress.
When used on an otherwise solid walls, such motifs are known as blind tracery, a decorative effect first applied on the west facade of the church of St Nicaise at Reims (1230s).
The arch of a lancet opening is often equilateral, but sometimes is much more acute, and when employed in the arcade of a choir apse, such as at Westminster Abbey, adds to the emphasis of height.
It is common that although the transepts of French churches do not project strongly, they are given visual importance almost equal to the west front, including large decorated portals and a rose window.
[dubious – discuss] These arches create a rich and lively effect when used for window tracery and surface decoration.
This type of arch, when employed as a window opening, lends itself to very wide spaces, provided it is adequately supported by many narrow vertical shafts.
[citation needed] Most 19th-century histories of Gothic architectural style used a series of typological categories based on the evolution of the dominant patterns of window tracery.
[10][11][12] In Gothic tracery, rounded quatrefoils have been used in modern industrial ornament which is used to embellish different parts of a building or certain objects.
Because of the cost and size limitations of parchment sheets, such designs would normally be drawn by incising onto a whitewashed board or a conveniently placed section of flat wall.
A number of churches and cathedrals still show the faint remains of these tracings (or épures as they are known in France), from where the mason's compass points scratched through the plaster and into the masonry below.
A number of major building sites (including Westminster Abbey, Wells Cathedral and York Minster) originally had dedicated tracery chambers, where the architects could prepare their designs in relative comfort.
The availability of a large flat floor surface meant that designs could be drawn life-size and the individual elements of bar tracery laid out on the plan to test their goodness of fit, before hoisting them up the scaffolding for installation in the actual window openings.
The high-quality carpentry and the inclusion of a garderobe and fireplace in the York tracing house also indicate the rising status of the architect around the 14th century.
