+ARCHITECTURAL DETAILS.+ While Arabic architecture, in Syria and Egypt alike, possesses more decorative than constructive originality, the beautiful forms of its domes, pendentives, and minarets, the simple majesty of the great pointed barrel-vaults of the Hassan mosque and similar monuments, and the graceful lines of the universally used pointed arch, prove the Coptic builders and their later Arabic successors to have been architects of great ability. The Arabic domes, as seen both in the mosques and in the remarkable group of tombs commonly called “tombs of the Khalîfs,” are peculiar not only in their pointed outlines and their rich external decoration of interlaced geometric motives, but still more in the external and internal treatment of the pendentives, exquisitely decorated with stalactite ornament. This ornament, derived, no doubt, from a combination of minute corbels with rows of small niches, and presumably of Persian origin, was finally developed into a system of extraordinary intricacy, applicable alike to the topping of a niche or panel, as in the great doorways of the mosques, and to the bracketing out of minaret galleries (Figs. 81, 82). Its applications show a bewildering variety of forms and an extraordinary aptitude for intricate geometrical design. [Illustration: FIG. 81.--MOSQUE OF KAÎD BEY, CAIRO] +DECORATION.+ Geometry, indeed, vied with the love of color in its hold on the Arabic taste. Ceiling-beams were carved into highly ornamental forms before receiving their rich color-decoration of red, green, blue, and gold. The doors and the _mimber_ were framed in geometric patterns with slender intersecting bars forming complicated star-panelling. The voussoirs of arches were cut into curious interlocking forms; doorways and niches were covered with stalactite corbelling, and pavements and wall-incrustations, whether of marble or tiling, combined brilliancy and harmony of color with the perplexing beauty of interlaced star-and-polygon patterns of marvellous intricacy. Stained glass added to the interior color-effect, the patterns being perforated in plaster, with a bit of colored glass set into each perforation--a device not very durable, perhaps, but singularly decorative.