A.D. 1300 to 1377. Reigns of Edward I., II., and III.
The transition from the Early English, or Lancet style, to the Decorated was much more gradual than from Norman to Early English, so gradual that it is impossible to draw a line where one style ceases and another begins. There can be no doubt that in some parts of the kingdom, Early English was in use at the same time that, in other districts, the Decorated style was becoming general, and thus the terms adopted to denote the different periods must not be taken as definite or as commencing or closing at any particular date, but merely as indicating the broad classification of the styles and details, and for associating them with particular reigns for convenience of study. The divisions are arbitrary, but very convenient in practice. Structurally, there was not a great change in the buildings, but there was a more harmonious relation and development of all the architectural features in walls, piers, buttresses, windows, etc., both with regard to their size and their enrichment, and it was because of this general use of ornament or enrichment that it is called the Decorated Period. "It rivals the preceding style in chasteness and elegance, while it surpasses it in richness."
Great progress was made in the reign of Edward I., and the Decorated work exhibits the most complete and perfect development of the Gothic arch, which in the Early English was not fully matured, and in the Perpendicular began to decline.
It is remarkable for its geometric tracery, its natural types of foliage, and the undulating character of line and form in its ornamental details.
_Windows._--The most distinctive features of the Decorated style are its large windows and its mouldings. The windows are the chief glory of the 14th century Gothic. They vary very considerably in size, in form and in intricacy.
As the window arches became broader, mullions or vertical bars of masonry were required for their support, dividing the windows into lights, and the upper portions of these mullions were developed into tracery, forming circles, trefoils, or other geometric figures, and, afterwards, flowing lines.
It has been shown how the grouping of lancet-shaped windows and the piercing of the space above them, under the arched dripstone, had produced "plate tracery." As the piercings became larger, narrow and irregularly shaped surfaces of stone were left. These were pierced, and the intervening piers of stone came to be shaped like the mullions; in fact, became a continuation of the mullions. This development, which was reached before the middle of the 13th century, is called "bar tracery." At first, this bar tracery was plain; then "cusps" (Pl. 40, Fig. 5), or projecting points, were introduced on the inner edge of the mullions, and added greatly to the rich effects. The earliest Decorated windows have tracery on a purely geometric basis. Exeter Cathedral is considered the best typical example of the early part of this style, and the existing windows were constructed at the end of the 13th century. The Chapter-houses at York and Southwell are other rich examples. Windows with flowing tracery are, in general, later than those with geometrical patterns, though they are sometimes contemporaneous in the same building.