ORCHESTRA (Gr. OpxhaTpa, which contains the same element as the verb Opxeicreal," to dance "), that part of the Greek theatre in which the chorus was situated—where the dances were performed. [THEATRE.] With the moderns, the orchestra is the place in the theatre allotted to the instrumental band, and that portion of a concert-room which is assigned to the musical performers, both instrumental and vocal. We not only apply the word to the place set apart for the musicians, but often use it to designate the whole of them collectively ; in which ease, orchestra and band are treated as synonymous terms.
Till the end of the 17th century or the beginning of the I8th, the instrumental performers of our theatres were stationed in a box on the side of the stage, and out of view of the greater portion of the spec tator& They were then few in number. But, however desirable in some respects, it would be impossible so to dispose of the large bands of the present day ; and all things considered, they could not be better placed than where they now are—just below the stage, so as not to interrupt the sight, and between the singer and the audience, thus enabling the former to have in view the conductor and leader—a matter of great importance in the musical drama, where all is sung by memory.
The orchestra of a concert-room should be so contrived that the front, when no passage beneath it is required, is about five feet higher than the level of the room, and it should rise rather steeply to the back, the corners of which ought to he rounded off, in order that the whole body of sound may be directly reflected. But the due appor tionment of the orchestra to the size and character of the room, and the requirements of the immense masses of vocal and instrumental performers now employed in the execution of oratorios, &c., is a matter that demands great knowledge of the laws of sound and considerable adaptive skill on the part of the architect. None of the great music halls yet constructed in this country can be considered as perfectly successful in this respect.
ORCHIL. Colouring matters of.]