<P> A further development was the flying buttress which arched externally from the springing of the vault across the roof of the aisle to a large buttress pier projecting well beyond the line of the external wall . These piers were often surmounted by a pinnacle or statue, further adding to the downward weight, and counteracting the outward thrust of the vault and buttress arch as well as stress from wind loading . </P> <P> The internal columns of the arcade with their attached shafts, the ribs of the vault and the flying buttresses, with their associated vertical buttresses jutting at right - angles to the building, created a stone skeleton . Between these parts, the walls and the infill of the vaults could be of lighter construction . Between the narrow buttresses, the walls could be opened up into large windows . </P> <P> Through the Gothic period, thanks to the versatility of the pointed arch, the structure of Gothic windows developed from simple openings to immensely rich and decorative sculptural designs . The windows were very often filled with stained glass which added a dimension of colour to the light within the building, as well as providing a medium for figurative and narrative art . </P> <P> The façade of a large church or cathedral, often referred to as the West Front, is generally designed to create a powerful impression on the approaching worshipper, demonstrating both the might of God and the might of the institution that it represents . One of the best known and most typical of such façades is that of Notre Dame de Paris . </P>

The gothic style was first associated with which of the following