[Illustration: FIG. 80.--SECTION OF CHURCH. _Carcassone._ WITH OUTER AISLES ADDED IN FOURTEENTH CENTURY.] The Gothic builders gave loftiness to their edifices by the use of spires and towers. They became very skilful in constructing them with buttresses below and pinnacles above, so that the spires should not detract from the apparent size of the buildings to which they were attached (Fig. 81). [Illustration: FIG. 81.--SPIRES OF LAON CATHEDRAL.] In the matter of design in ornament the Gothic order had no fixed method, except so far as its forms were symbolic. Every form of vegetable design was employed; vines and leaves were abundant. As a rule the use of human forms or animals as supports to columns or other weights was avoided. If they were introduced the animals were not reproductions of such as exist, but the imaginary griffin or other monster, and at times dwarfs or grotesque human beings, were represented as if for caricatures. Sculptured figures were usually placed upon a pedestal either with or without niches for them, and were not made to appear to be a part of the building itself. The deep recesses of Gothic portals, the pinnacles and niches gave opportunities to display exterior sculpture to great advantage (Fig. 82). The interiors were also appropriate for any amount of artistic ornament in bas-reliefs or figures that could be lavished upon them. [Illustration: FIG. 82.--PORTAL OF THE MINORITES' CHURCH. _Vienna._] The most original and effective feature of ornament, however, which was introduced by Gothic architects is that of painted glass. To this they devoted their best talent. It is not necessary to say how beautiful and decorative it is; we all know this, and our only wonder is that it was left for the Gothic architects to apply it to architectural uses. We do not know precisely when stained or painted glass was invented, but we know that it existed as early as 800, and came into very general use in the eleventh and twelfth centuries. [Illustration: FIG. 83--EXTERNAL ELEVATION, CATHEDRAL OF PARIS.] Before painted glass was used windows were made very small, and it was some time before the large, rich style was adopted. The following cut from Notre Dame, at Paris, gives the three stages of the change, and it is interesting to see them thus in one church (Fig. 83). On the left are the undivided windows without mullions or dividing supports; next, at the right, the upper window shows the form with one perpendicular mullion and a circular or rose window above the centre; lastly, on the right of the lower story we see a full traceried window.