'MOORISH ARCHITECTURE.
A kind of mosaic \YOH: was common on the exteriors of some of the mediaeval churches of Italy, as the Duomo at Pisa, where the walls of the façade are decorated with a sort of pattern in black and white colours, brilliant reds and Hiles being interspersed occasionally. Another instance of external decoration in mosaic is to be seen in the facade of St. Mark's, Venice.
Pietures in mosaic, properly so termed, and which are of eimipanniyely recent introduction, dit•r from the above in being merely copies or file-similes of paintings, approaching in appearance as nearly to pictures as possible. This style of mosaic work dates only from the commencement of the seventeenth century. The tints arc .1r fr(an to darker shades by using an indefinite 11111111)er of very small pieces of glass of various intensities of odour, so placorthat those pieces which are contiguous exhibit scarcely any ceptible dill'erence to the eye. In the more ancient mosaics the tints are not blended one into the other, but kept quite distinct, the outlines being hard, and flue joints between the tessent plainly visible. in these examples there is no
attempt at making pictures ; they are treated in a con ventional manner, so that such features are to be considered as characteristic proprieties rather than defects.
Florentine work may also be added to the list of mosaics; it is employed principally in the inlaying of marble slabs for and work upon a nunlerate scale.
One description of mosaic work is that of introducing, along with the finest marbles, the richest of precious stones, lapis lazuli. agates, cornelians, emeralds, turquoises, &c. The practice of making mosaics with coloured glass and metals is now little in use, though of surprising lustre and durability ; but that of marbles alone is in common use ; the mosaic in precious stones being so very dear, that the few workmen who apply themselves to it, make little else but petty works, as ornaments for altar-pieces, tables for rich cabinets. &e.