Cut-work, as it is called, is often employed in decorations. Various figures, letters, garlands, &c. may be represented. This may also be accomplished in tambour-work. Several methods have been used to produce the same effect. Cut-work, made in pasteboard, and the pasteboard blackened and suspended in a frame, will, by the aid of lights placed behind it, exhibit the design very perfectly. A figure of a sun cut out of pasteboard, either fixed or made to revolve in the manner before described, and illuminated by fixed lights or revolving cases, is considered to be the best mode of forming such pieces. In all instances, the more brilliant the fire, the more perfect is the representation. Tambour decorations are variously arranged; and, frequently, in the termination of an exhibition, six or more are shown at once, and sometimes with cascades, and turning suns.
In the place of cut-work, painted transparencies, made with fine colours, and on Florence Taffeta, are usually employed. Transparent paintings however, are not preferred by some, as the effect, it is said, is not so perfect as when cut-work is employed. Morel gives a preference to the latter.
Transparencies may be formed with silk, or fine linen, and even with paper, if previously prepared, by means of the spirit of turpentine. The colours are painted in turpentine, and transparent varnish is then applied.
Transparent screens may be prepared, by spreading white wax, dissolved in spirits of turpentine, over thin muslin. A screen, thus prepared, will roll up without injury. A clearer screen may be produced, by having the muslin stretched upon a rectangular frame, and prepared with turpentine instead of wax.
In the Œuvres de Diderot, t. xv, p. 349, are observations respecting transparencies, and the manner of preparing them. The process described is nothing more than we have noticed. It consists in using the oil of turpentine, and sometimes a solution of wax in turpentine. The colours are prepared mostly with turpentine. Canada balsam, thinned by the addition of the spirit, is also employed. Moveable transparencies were exhibited with great effect in Paris. Transparent figures were made to move continually in every direction, which had a singular appearance. Artificial fire-works were very accurately imitated, by producing a variety of movements with different pieces of transparencies, variously coloured. The sun, moon, and stars, revolving wheels, &c. composed a part of this exhibition.
With respect to decorations in white and coloured lances, we may observe, that artificial fire-works are usually terminated by some decoration, which corresponds with the subject. For this purpose, triumphal arches, fronts of palaces, colonades, rocks, &c. are formed, and represented in wood-work. These are usually clothed, and painted in water-colours. From the rocks, water is made to issue, forming cascades, and a number of figures are put in motion. The jets of water are terminated by jets of Chinese fire, or brilliant fire-rain.
The furniture, or decorations, may be various, either with white or coloured lances of illumination, hung four inches apart, and attached to different parts of the figure, or building. If it is in front of a temple, the columns are ornamented with emblems, &c. the fire-work being thus arranged: viz. blue lances are attached to the columns, white lances to their entablature, and to the emblems, yellow lights. This however, depends on taste.
Decorations are also made with matches; but this mode is not preferred, because so much smoke is thereby produced.
Figures, cut in paper, are illuminated in the manner before described. But for this purpose, muslin is first stretched on a frame, and its sides are covered with two or three thicknesses of paper, which are pasted on. It is then blackened. After tracing the design, or the subject of the illumination, and cutting it out with exactness, the frame is put in a case, sufficiently deep to contain a number of lights.
Illuminations, as an expression, of public feeling for some event or memorable occasion, are by no means a recent thing. Various modes have been adopted to render such exhibitions more elegant, as well as more expressive. Hence, with the usual display of lights, arranged according to taste and fancy, transparencies, decorations, such as we have described, &c. have been more or less customary.