e
during the last fifty years than in any previous three centuries. We
are literally correct in saying that a veritable revolution has already
been effected--and the end is not yet.

As leaders in this revolutionary movement, three names stand out with
startling prominence--Henry Willis, Aristide Cavaille-Coll and Robert
Hope-Jones.

Others have made contributions to detail (notably Hilborne L.
Roosevelt), but it is due to the 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, Cavaille-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 t