Another article w Inch has of late been introduced as a substitute for the above materials, is embossed leather, which in some instances is superior to either of them. It can be made to assume any degree of relief short of' the complete round, and it preserves all the sharpness and fineness of out line possessed by the mould from which it is east. The moulds in this process are of metal, into which the leather previously prepared by steaming, is forced by a combination of hydraulic and pneumatic pressure, by which extraordinary power the finest lines on the mould are repeated with the greatest accuracy on the copy. It might be supposed from the nature of the material, that this delicacy of outline would be deteriorated by time, or that the east might be altogether destroyed by damp; but there is really no ground for appre hensions of this nature, as the casts are found under all circumstances to preserve, undiminished in the minutest details, the form transferred to them from the original mould, and to be improved and hardened rather than injured by age. This material has an advantage in the fiteility with which it can be made to imitate old carved work ; indeed, when intro duced in the restoration of such works, it is difficult to distinguish the original from the imitation ; it may be coloured or gilded as desired. It is applicable to all kinds of interior decorations, such as cornices, friezes, &e., and has
been employed even in the entire paneling of rooms.
Another material which, until very recently, was entirely unknown to us, hut which, since its liNt introduction, has conic into extensive use, threatens to prove a formidable rival to the above-mentioned artieles—we allude to Gutta Percha. This substance has not been tested sufficiently to allow us to speak decidedly as to its applicability to the pur poses we are considering; it is moulded into cornices, panels, and other forms of architectural decoration, and is on many accounts eligible for such uses ; it can be moulded, cast, stamped, or embossed, into any form however elaborate, and is susceptible of colour ; it has, however, disadvantages which for the present must preclude its employment ; for, although it promises considerable hardness, it is readily injured by contact with any sharp body ; besides this, it is liable to soften and liquify when exposed to an elevated temperature. This last defect has been modified by a process to which the material is subjected in its manufacture, which is termed metallo-thionising, but still it has not been entirely removed. The properties of this production, however, have not yet been sufficiently developed to decide upon its capabilities ; many improvements will doubtless be introduced into its manufacture, as its nature becomes more fully understood.