Organ

the noblest of musical instruments. In some form the organ was known in the remotest antiquity. It is a development of the ordinary whistle. In place of a single whistle blown by the breath, the organ consists essentially of three parts,--pipes, a reservoir of compressed air, known as wind, and, lastly, the action, a mechanical arrangement, including the keyboard and pedals, by which the air is admitted to the tubes. The note given forth by a pipe depends on its length. Doubling the length of a tube produces a note an octave lower. Thus pipes two feet, four feet, eight feet, and sixteen feet in length produce notes successively an octave apart. A series of pipes comprising usually an octave is known as a stop. An organ consists usually of many stops. So much for the pitch.

The quality of the note is determined by the size and material of the pipe. The pipes of any one set or stop are supposed to be alike as to quality. Metal pipes, wooden pipes, broad pipes, and narrow pipes give notes differing in quality. There is a difference also between a note produced by a current of wind playing across the open end of the pipe and that produced by a metallic tongue set in vibration. Wind is contained in a reservoir of compressed air filled by a bellows. The reservoir may be filled before playing commences or, in the case of a large organ requiring much wind, an assistant, out of sight, of course, works the bellows and keeps the reservoir filled; or wind is supplied by machinery. In the case of a small, so-called parlor organ, the reservoir is kept full by working a pedal with the foot. A series of tubes opened and closed by means of a keyboard permits the organist to bring pipes into play as he may desire. The modern organ has the range of a brass band. The trombone, the piccolo, the flute, and even the violin and the melodeon are represented. The costly part of an organ is not in sight. Among the interior contrivances are delicate belows an inch in length as sensitive as the scientist's scales.

Up to the sixteenth century, the organ was used as an accompaniment for the human voice. The organs of the medieval cathedrals were used as accompaniments for chants. Organ music then began to take on a new character. Many composers, especially Sebastian Bach, have written music for the organ alone. Though used in concert halls and opera houses, the organ is still preeminently the instrument of church service. One of the chief charms of an old cathedral is the organ. Organ screens-curtains of wood or stone-are traditionally the richest specimens of the sculptor's art. The organ of St. Peter's, Rome, has 100 stops. The organ in Seville Cathedral has 5,300 pipes. The largest organ ever built is in the town hall of Sydney. It has 8,000 pipes,-the largest, a contra-trombone, is sixty-four feet long; the smallest is a fraction of an inch in diameter. This organ occupies a space eighty-five feet long by twenty-six feet wide. The largest in London is in Albert Hall. The largest in America is in Salt Lake City. Notable organs are those in the Roman Catholic cathedrals at Montreal and Boston. Other notable organs are those in the Music Hall at Cincinnati and in Tremont Temple, Boston. The organ, in essentially its present form, is said to have been perfected at Alexandria about 200 A.D. Charlemagne had an organ in his cathedral at Aix-la-Chapelle.