DIORAMA, a mode of painting and scenic exhibition invented a few years ago by two French artists, Dagnerre and Bouton. The peculiar, and almost magical effect of the diorama arises. in a great degree, from the contrivance em ployed in exhibiting, the painting. which is viewed through a large opening or proscenium. Within this proscenium the picture is placed at such a distance, that the light is thrown upon it, at a proper angle from the roof, which is glazed with ground glass, and cannot be seen by the spectators. \Viui'e the light is thus concentrated on the picture. the spectators are left in comparative darkness. by which the elicit is increase] : and the illusion is rendered still inure complete, by the skilful manner in which the transitions of light are managed. The light may he diminished or increased at pleasure, and th it either gra hall v or suddenly, so as to represent the change from ordinary daylight to sunshine, from sun-I-line to cloudy weather, or to the obscurity of twilight, and also the difil.renee of atmospheric tone attending them. By means of different folds or shutters attached th,. glazed transitions are produred in regard to light and atmos pheric effects of the ((lost pleasing character. The diorama is in Iced a most p.•rfeet scenic representation of nature ; by varied and ingenious contrivances, it is capable of displaying the greatest difference in its pictures. It is pceuliarly adapted for moonlight subjects. and for exhibiting such "accidents" in landscapes as sudden gleams of sunshine and their dis appea .ance. For showing architecture, particularly interiors, it is unrivalled, as powerful relief may be obtained without that in the shadows which is almost (net (table in every other mode of painting. Althongh as yet only employed tor purpose: of pn blie exhibit ion, the diorama might undoubtedly he made use of tor the PalhollishIlWat of such parts ail building as corridors and the like, where liLit, can only be obtained flout one extremity.
The Diorama in the Regent's Park, was erected fb• the rf pictures with the IlIcek we have been describing; and a= one of the roost and remarkable of the " sights in London," de:I-ryes a passing notice.
The pictures exhibited arc each about feet long, and 42 !let wide, and are capable of being shifted ;up] exchanged for others when required. They are placed at distances from the spectator proportioned to the angle at which he would view the object in nature ; and by the united talents or the artist and the machinist, the illusion is rendered so perfect, and so true to nature, that the beholder is almost led to doubt that they are really the efIect of art. Thus, in
subjects, as the interior of the cathedral, the whole is at one moment sublimed by gloom, as by the overshadowing of some passing cloud. The " long drawn aisle '' and recesses are obscured, all seems about to be buried in darkness, when, in an instant, as though the interruption had passed away, and the bright light or day was permitted to shine through the windows in its full lustre, the Gothic architecture is illumined in the most beautifid manner, the shadows pro jected with force and truthond the secondary lights produced beneath the groinings of the roof in all the delicate grada tions of natural reflections. Landscape scenes undergo similar changes, and atImbrable efrects are produced in the transitions from shade and darkness, to the brightness of light and sunshine.
The elevation of the building was designed by Mr. Nash ; it is of the Ionic order, the basement embellished with columns and pilasters, &c., the centre of which is the approach to the theatre. The building consists of a vesti bule and two lateral houses, facing a circular part of the edifice, which may be regarded as the audience-room of the theatre, and is occupied by boxes, and an open area tbr spectators. The sides of this circular part are painted and with festooned draperies, and the top is covered with a transparent !tainting, divided into many compartments. and charged with medallion likenesses of several eminent artists. Over this semi-transparent ceiling, or inner roof. rises a coni cal roof. nearly half of which is glazed. The circular part consists of a wall, two-thirds of a circle, with two small doorways, and two large openings to the compartments of the scenic theatre. Immediately within this wall, but detached from it, is another wall. rising from the floor to the inner ceiling, and which, with the floor, revolves on a pivot beneath. A large square opening. like the proscenium of a theatre, allows the audience to view the pictures.
The Diorama was opened to the public in October, 1S23, and has ex er since Continued to be visited as one Of the most popular exhibitions in the metropolis.