The Recent Revolution in Organ Building | Page 6

genius, the inventions and the work of those three great men that the modern organ stands where it does to-day.
We propose:
1. To enumerate and describe the inventions and improvements that have so entirely transformed the instrument;
2. To trace the progress of the revolution in our own country; and,
3. To describe the chief actors in the drama.
In the middle of the last century all organs were voiced on light wind pressure,[3] mostly from an inch and a half to three inches. True, the celebrated builder, William Hill, placed in his organ at Birmingham Town Hall, England, so early as 1833, a Tuba voiced on about eleven inches wind pressure, and Willis, Cavaillé-Coll, Gray and Davison, and others, adopted high pressures for an occasional reed stop in their largest organs; yet ninety-nine per cent. of the organs built throughout the world were voiced on pressures not exceeding three and one-half inches.
In those days most organs that were met with demanded a finger force of some twenty ounces before the keys could be depressed, when coupled, and it was no uncommon thing for the organist to have to exert a pressure of fifty ounces or more on the bass keys. (The present standard is between three and four ounces. We are acquainted with an organ in New York City which requires a pressure of no less than forty ounces to depress the bass keys.)
The manual compass on these organs seldom extended higher than f|2| or g|3|, though it often went down to GG.[4]
It was common to omit notes from the lower octave for economy's sake, and many stops were habitually left destitute of their bottom octaves altogether. Frequently the less important keyboards would not descend farther than tenor C.[5]
The compass of the pedal board (when there was a pedal board at all) varied anywhere from one octave to about two and a quarter octaves. The pedal keys were almost invariably straight and the pedal boards flat.
[Illustration: Fig. 4. Nomenclature of Organ Keyboard]
[1] The invention of the pneumatic lever has been claimed for Mr. Hamilton, of Edinburgh, Scotland. It is, however, generally credited to Barker and known as the "Barker pneumatic lever." (See also note about Joseph Booth, page 129.)
[2] Barker was also associated with Péschard, who in 1864 patented jointly with him the electro-pneumatic action. (See page 37.)
[3] The pressure of the wind supplied by the old horizontal bellows is regulated by the weights placed on top. The amount of this pressure is measured by a wind-gauge or anemometer invented by Christian F?rmer about 1677. It is a bent glass tube, double U shaped, into which a little water is poured. On placing one end of it fitted with a socket into one of the holes in the wind-chest (in place of a pipe) and admitting the wind from the bellows the water is forced up the tube, and the difference between the level of the surface of the water in the two legs of the tube is measured in inches. Thus, we always talk of the pressure of wind in an organ as being so many inches.
[4] The organ in Great Homer Street Wesleyan Chapel, Liverpool, England, had manuals extending down to CCC. It was built for a man who could not play the pedals and thus obtained 16 ft. tone from the keys. The old gallery organ in Trinity Church, New York, also has this compass.
[5] Tenor C is the lowest note of the tenor voice or the tenor violin (viola). It is one octave from the bottom note of a modern organ keyboard, which is called CC. The lowest note of the pedal-board is CCC. Counting from the bottom upwards on the manual we have, therefore, CC (double C), C (tenor C), c (middle C), c|1| (treble C), c|2| (C in alt) and c|3| (C in altissimo). This is the highest note on the keyboard of 61 keys. According to the modern nomenclature of the pianoforte keyboard this note is c|4|, and is frequently so stated erroneously in organ specifications.
GG is four notes below CC, the break in the scale coming between GG and FFF. Tenor C is an important note to remember. Here is where the cheap builder came in again. He cut his stops short at tenor C, trusting to the pedal pipes to cover the deficiency.
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[Illustration: PROSPER-ANTOINE MOITESSIER, INVENTOR OF TUBULAR PNEUMATIC ACTION]
In the year 1845, Prosper-Antoine Moitessier, an organ-builder of Montpellier, France, patented what he called "abrégé pneumatique," an organ action in which all back-falls and rollers were replaced by tubes operated by exhaust air. In 1850 he built with this action an organ of 42 speaking stops for the church of Notre Dame de la Dalbade at Toulouse. This organ lasted 33 years. In 1866 Fermis, schoolmaster and village organist