Page:Popular Science Monthly Volume 40.djvu/662

642 Among the special effects in this organ not specified are a bassdrum and tympani (kettle-drums), also operated by pneumatic agency. The great and swell organs are on a four-inch wind; the choir is on a three-inch; the thirty-two-foot and sixteen-foot open diapasons are on a seven-inch wind. In the region of tones may be found a German gamba—a unique stop with a string tone—and a vox humana copied from the celebrated instrument at Freiburg by Mooser. The vox anglica in the organ treated on is a remarkable expression effect, while the song-trumpet stop is a startling acoustic development. It is of such immense power that it is capable of leading eight thousand voices. The instrument also contains combination piston-knobs under the key-board and a combination pedal to every organ. These are adjustable. There are in all 110 stops and 4,448 pipes, divided as follows: Great organ, 18 stops, 1,464 pipes; swell organ, 18 stops, 1,342 pipes; choir organ, 12 stops, 854 pipes; solo organ, 8 stops, 488 pipes; pedal organ, 10 stops, 300 pipes; also 10 couplers, 11 mechanical movements, 6 pneumatic piston-knobs in great organ, 11 combination pedals, and 6 pedal movements.

The four manuals contain five octaves each, with an auxiliary pedal compass of two and a half octaves. The wind is furnished by three immense bellows of various wind pressure, operated by a C. & C. electric motor of an improved order on an Edison circuit. Its exterior, moreover, is most striking. It shows a fagade of richly decorated pipes forty feet in width and fifty feet in height, and is altogether one of the finest instruments in appearance and effect in this country, and an imposing exemplification of American organ-building.

—Sound is produced in instruments such as the French and English harmonium and the American parlor organ through the medium of the free reed. The latter, though related to the former in a physical and mechanical sense, is in many respects so different from the European reed instruments of the class designated that it is entitled to stand alone as an instrument peculiarly American and distinct in point of construction.

The individuality of the American parlor organ rests largely upon the system of reed structure invented in this country, upon which a tone has been evolved which is easily distinguished from that produced by the reed instruments made abroad. Several other features in its interior construction and exterior finish, however, distinguish it from the reed instruments called harmoniums produced in Europe. The "free reed," as it was first applied in American accordeons and seraphines, was not by any means a domestic invention, as writers recklessly assert. It was used by European pipe-organ builders for stop effects, and also in a