_The American Organ_ acts by wind exhaustion. A vacuum is practically
created in the air-chamber by the exhausting power of the footboards,
and a current of air thus drawn downwards passes through any reeds
that are left open, setting them in vibration. This instrument has
therefore exhaust instead of force bellows. Valves in the board above
the air-chamber give communication to reeds (fig. 2) made more slender
than those of the harmonium and more or less bent, while the frames in
which they are fixed are also differently shaped, being hollowed
rather in spoon fashion. The channels, the resonators above the reeds,
are not varied in size or shape as in the harmonium; they exactly
correspond with the reeds, and are collectively known as the
"tube-board." The swell "fortes" are in front of the openings of these
tubes, rails that open or close by the action of the knees upon what
may be called knee pedals. The American organ has a softer tone than
the harmonium; this is sometimes aided by the use of extra resonators,
termed pipes or qualifying tubes, as, for instance, in Clough &
Warren's (of Detroit, Michigan, U.S.). The blowing being also easier,
ladies find it much less fatiguing. The expression stop can have
little power in the American organ, and is generally absent; the
"automatic swell" in the instruments of Mason & Hamlin (of Boston,
U.S.) is a contrivance that comes the nearest to it, though far
inferior. By it a swell shutter or rail is kept in constant movement,
proportioned to the force of the air-current. Another very clever
improvement introduced by these makers, who were the originators of
the instrument itself, is the "vox humana," a smaller rail or fan,
made to revolve rapidly by wind pressure; its rotation, disturbing the
air near the reeds, causes interferences of vibration that produce a
tremulous effect, not unlike the beatings heard from combined voices,
whence the name. The arrangement of reed compartments in American
organs does not essentially differ from that of harmoniums; but there
are often two keyboards, and then the solo and combination stops are
found on the upper manual. The diapason treble register is known as
"melodia"; different makers occasionally vary the use of fancy names
for other stops. The "sub-bass," however, an octave of 16 ft. pitch
and always apart from the other reeds, is used with great advantage
for pedal effects on the manual, the compass of American organs being
usually down to F (FF, 5 octaves). In large instruments there are
sometimes foot pedals as in an organ, with their own reed boxes of 8
and 16 ft. the lowest note being then CC. Blowing for pedal
instruments has to be done by hand, a lever being attached for that
purpose. The "celeste" stop is managed as in the harmonium, by rows of
reeds tuned not quite in unison, or by a shade valve that alters the
air-current and flattens one row of reeds thereby.
Harmoniums and American organs are the result of many experiments in
the application of free reeds to keyboard instruments. The principle
of the free reed became widely known in Europe through the
introduction of the Chinese cheng[1] during the second half of the
18th century, and culminated in the invention of the harmonium and
kindred instruments. The first step in the invention of the harmonium
is due to Professor Christian Gottlieb Kratzenstein of Copenhagen, who
had had the opportunity of examining a cheng sent to his native city
and of testing its merits.[2] In 1779 the Academy of Science of St
Petersburg had offered a prize for an essay on the formation of the
vowel sounds on an instrument similar to the "vox humana" in the
organ, which should be capable of reproducing these sounds faithfully.
Kratzenstein made as a demonstration of his invention a small
pneumatic organ fitted with free reeds, and presented it to the
Academy of St Petersburg.[3] His essay was crowned and was republished
with diagrams in Paris[4] in 1782. Meanwhile, in 1780, a countryman
of Kratzenstein's, an organ-builder named Kirsnick, established in St
Petersburg, adapted these reed pipes to some of his organs and to an
instrument of his invention called organochordium, an organ combined
with piano. When Abt Vogler visited St Petersburg in 1788, he was so
delighted with these reeds that in 1790 he induced Rackwitz, an
assistant of Kirsnick's, to come to him and adapt some to an organ he
was having built in Rotterdam. Three years later Abt Vogler's
orchestrion, a chamber organ containing some 900 pipes, was completed,
and, according to Rackwitz,[5] was fitted with free-reed pipes. Vogler
himself, however, does not mention the free reed when describing this
wonderful instrument and his system of "simplification" for church
organs.[6] To Abt Vogler, who travelled all over Germany, Scandinavia
and the Netherlands, exhibiting his skill on his orchestrion and
reconstructing many organs, is due the credit of making Kratzenstein's
invention known and inducing the musical world to appreciate the
capabilities of the free reed. The introduction of free-reed stops
into the organ, however, took a secondary place in his scheme for
reform.[7] Friedrich Kaufmann[8] of Dresden states that Vogler told
him he had imparted to J. N. Malzel of Vienna particulars as to the
construction of free-reed pipes, and that the latter used them in his
panharmonicon,[9] which he exhibited during his stay in Paris from
1805 to 1807. Kaufmann suggests that it was through him that G. J.
Grenie obtained the knowledge which led to his experiments with free
reeds in organs. It is more likely that Grenie had read Kratzenstein's
essay and had experimented independently with free reeds. In 1812 his
first _orgue expressif_ was finished. It was a small organ with one
register of free reeds--the expression stop, in fact, added to the
pipe organ and having a separate wind-chest and bellows. It would seem
from his description of the orchestrion in _Data zur Akustik_ that
Vogler knew of no such device. He used the swell shutter borrowed from
England and a threefold screen of canvas covered with a blanket
arranged _outside the instrument_, neither of which is capable of
increasing the volume of sound from the organ, or at least only after
having first damped the sound to a pianissimo. Vogler explains
minutely the apparatus used to conceal the working of the screen from
the eyes of the public.[10] The credit of discovering in the free reed
the capability of dynamic expression was undoubtedly due to Grenie,
although Abt Vogler claims to have used compression in 1796,[11] and
Kaufmann in his choraulodion in 1816. A larger _orgue expressif_ was
begun by Grenie for the Conservatoire of Paris in 1812, the
construction of which was interrupted and then continued in 1816.
Descriptions of Grenie's instrument have been published in French and
German.[12] The organ of the Conservatoire had a pedal free-reed stop
of 16 ft., with vibrators 0.240 m. long, 0.035 m. wide, and 0.003 m.
thick.[13] Two compressors, one for the treble and the other for the
bass, worked by treadles, enabled the performer to regulate the
pressure of wind on the reeds and therefore to obtain the gradations
of forte and piano which gained for his instrument the name of _orgue
expressif_. Grenie's instrument was a pipe organ, the pipes
terminating in a cone with a hemispherical cap in the top of which was
a small hole. There were eight registers including the pedal, and the
positive on the first keyboard had reed stops furnished with beating
reeds. Biot insists on the Importance of the regulating wires (Fr.
_rasettes_; Ger. _Krucken_) for determining the vibrating length of
the reed tongue and maintaining it invariable. These are clearly shown
in his diagram (see article FREE REED VIBRATOR, fig. 1); they do not
essentially differ from those used with the beating-reed stops in his
organ (fig. 76, pl. II.), or indeed from those figured by Praetorius.
Isolated specimens of the cheng must have found their way to Europe
during the 15th and 16th centuries, for Mersenne[14] depicts part of
one showing the free reed. It would seem that still earlier in the
17th century there was an organ in a monastery in Hesse with free
reeds for the _Posaune_ stop, for Praetorius gives a description of
the "extraordinary" reed (p. 169); there is no record of the inventor
in this case.
During the first half of the 19th century various tentative efforts in
France and Germany, and subsequently in England, were made to produce
new keyboard instruments with free reeds, the most notable of these
being the physharmonica[15] of Anton Hackel, invented in Vienna in
1818, which, improved and enlarged, has retained its hold on the
German people. The modern physharmonica is a harmonium without stops
or percussion action; it does not therefore speak readily or clearly.
It has a range of five to six octaves. Other instruments of similar
type are the French melophone and the English seraphine, a keyboard
harmonica with bellows but no channels for the tongues, for which a
patent was granted to Myers and Storer in 1839; the aeoline or
aelodicon[16] of Eschenbach; the melodicon[17] of Dietz; the
melodica[18] of Rieffelson; the apollonicon;[19] the new cheng[20] of
Reichstein; the terpodion[21] of Buschmann, &c. None of these has
survived to the present day.
The inventor of the harmonium was indubitably Alexandre Debain, who
took out a patent for it in Paris in 1840. He produced varied timbre
registers by modifying reed channels, and brought these registers on
to one keyboard. Unfortunately he patented too much, for he secured
even the name _harmonium_, obliging contemporary and future
experimenters to shelter their improvements under other names, and the
venerable name of organ becoming impressed into connexion with an
inferior instrument, we have now to distinguish between reed and pipe
organs. The compromise of reed organ for the harmonium class of
instruments must therefore be accepted. Debain's harmonium was at
first quite mechanical; it gained expression by the expression-stop
already described. The Alexandres, well-known French makers, by the
ingenuity of one of their workmen, P. A. Martin, added the percussion
and the prolongement. The melody attachment was the invention of an
English engineer; the introduction of the double touch, now used in
the harmoniums of Mustel, Bauer and others--also in American
organs--was due to Tamplin, an English professor.
The principle of the American organ originated with the Alexandres,
whose earliest experiments are said to have been made with the view of
constructing an instrument to exhaust air. The realization of the idea
proving to be more in consonance with the genius of the American
people, to whom what we may call the devotional tone of the instrument
appealed, the introduction of it by Messrs Mason and Hamlin in 1861
was followed by remarkable success. They made it generally known in
Europe by exhibiting it at Paris in 1867, and from that time
instruments have been exported in large numbers by different makers.
(A. J. H.; K. S.)