ORGAN — Hydraulus graffito on the wall of a Roman house discovered beneath the basilica of St Sebastian (c. 111 AD) with a ganista and people at the bellows — Rome.
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ORGAN. — A wind instrument with sounding pipes (from about ten in primitive ones to several thousand in modern ones) of varying size, shape and material (metal, wood, etc.), grouped according to their timbre into registers. The sound is produced either by the air vibrating in the body of the pipes and is all the deeper the higher the column of vibrating air (the other characteristics of the pipe: diameter, cylindrical, conical shape, etc., only affect the timbre) or by a vibrating reed inserted in the foot of the pipe, which serves only to balance the sonorities emitted by the reed. The current of air required, generated by mechanical means (pumps, bellows, fans), is forced into the windchests, the vital ganglia of the organ, constructed with various systems (slider, tracker, cone-valve, membrane, electric, etc.); on these are arranged, in rows, the pipes of the same kind and shape, and of progressive size. The windchests are connected by the action (mechanical or tracker, tubular, electric) to the console at the organist’s disposal and which carries the keyboards (from one to five, in exceptional cases up to seven, with a varying number of keys), the pedalboard (with a maximum of 32 pedals), the mechanisms for operating the stops and all other devices that facilitate the handling of the instrument or amplify its sound resources (foot levers, couplers, unions, reversible pistons, pistons, collective controls, cancellers, free and preset combinations, stirrups, etc.).
The organ arose from the addition of an air reservoir, as in the bagpipe, to the Pan-pipes. In its two-thousand-year evolution it has undergone the most surprising technical and tonal transformations.
The ugabh of the Bible, organum in the Vulgate, a term retained in the new translation of the Psalter, generically denotes a wind instrument. A primitive organ with bellows may have been the maghribhah mentioned in the Talmud. According to A. Kircher (Musurgia universalis, Rome 1650) the same genus includes the maghribhah (Dan. III, 5, 7, 10, 15), though his description of it is fanciful. But the history of the organ begins with the hydraulus, so called from the use of water to balance the pressure of the air produced by pumps. Invented by Ctesibius, who lived under the reign of Ptolemy I (246–21 BC), it is described by Hero of Alexandria in Pneumatica, I, 42. Ancient Arabic sources preserve, under the name of Muristus, Greek treatises, including a description of the hydraulic organ, perhaps by Ctesibius himself. In any case, Eastern sources provide no information about instruments of this kind prior to the hydraulus. In the one described by Vitruvius (De architectura, X, 13, 1–6), groups of pipes can be selected at will. This characteristic is confirmed by the discovery at Aquincum (1931) of the remains of an authentic Roman organ. Each group of pipes was controlled by a perforated slider, moved by a handle between the boards of the windchest lengthwise. The analogy with the mechanism of the stops in the slider windchest is evident. In the hydraulus, however, the individual groups of pipes do not select, as in the stops, different timbres, but different pitches or modes. Other perforated sliders, placed above the former but running along the depth of the windchest, were connected to the keys; when the holes in the sliders coincided with those in the boards of the windchest, the pipes sounded. These latter, very different from modern ones, were labial pipes of small proportions, largely covered and of narrow scale, made of a laminated brass alloy. They had to sound at high pressure because they were reinforced with rings. The hydraulus enjoyed great diffusion, especially as a secular instrument, and is reproduced in numerous archaeological monuments, such as the famous terracotta found at Carthage in 1885 and the graffiti discovered in 1928 beneath the basilica of St Sebastian in Rome, etc. (cf. C. Mercurelli, Hydraulus graffito su epigrafe sepolcrale del cementerio di Commodilla, in Riv. Arch. Crist., 15 [1938], pp. 43–106). The obelisk of Theodosius (d. 393) in Constantinople reproduces a bellows organ.
It seems that the Roman organ disappeared with the barbarian invasions. It survived in the East, from where it returned to Europe; in the year 757, all the annals record twenty organa in Francia, an admired gift from the Emperor Constantine Copronymus to Pepin. In 826, Balderic, Margrave of Friuli, brought to Louis the Pious the Venetian priest George, a builder of organs in the Greek manner, who was commissioned to construct one in Aachen. But only the discovery of the ventilabrum (also called paravento), the valve that would replace, in all its functions, the holes of the sliding sliders used in the hydraulus, allowed the medieval organ to develop. It became the object of study, and monks wrote the first theoretical treatises on its construction (De mensura fistularum, 9th cent., Paris, Bibliothèque nationale, ms. lat. 12049, fol. 43; Incipit ordo fistularum of the anonymous of Bobbio, Milan, Biblioteca Ambrosiana). With due reservations, certain notices about the use of the organ deduced from unreliable documents must be accepted.
In the 13th century, under the impulse of the Ars nova, the organ made notable progress and the extremely agile portative (portable organ) became widespread, played with the right hand while the left pressed the bellows. There is abundant iconography on this in the paintings of the time, from Giotto onwards. From these reproductions it also emerges that portatives were equipped with handles, certainly to select the stops or to open access to certain low pipes called bourdons (in the allegory of Music by Andrea da Firenze c. 1355, in the Cappellone degli Spagnoli in S. Maria Novella in Florence, on the side of the instrument four handles can be seen, and in the Coronation of the Virgin by Caterino Veneziano, in the Accademia in Venice, three are depicted).
From the development of the portative arose the positive, of larger proportions, with a more extended keyboard to be played with both hands. It rested on a table, whence its name, and later on a base that contained the bellows. With the positive, the slider windchest (tracker action) took on its definitive form. At the same time, the large church organ, born of environmental needs, assumed its own character.
Gradually, instruments with national characteristics began to assert themselves. Especially in Flanders, the large organ took on the appearance of a complete sound mass, not susceptible to variations in intensity; hence the need soon arose to add another separate body, with less powerful sonority but capable of being modified through registration, such as in the positive. This new body would be placed behind the organist’s back and was called the *positivo tergale*. From this first innovation came the introduction of all the other bodies placed above or below the main windchest. In the French school, various bodies were also employed, but with distinctly coloristic functions. Italy, however, perhaps because its organs had earlier than in other countries learned to select in individual stops the compact mass of the large organ, did not feel the need to add other bodies to the fundamental nucleus; thus its classical instruments were always with a single keyboard. Even though classical Italian organ music did not give particular importance to the pedal, Italian organs had had a pedalboard since the fourteenth century, which therefore was not brought to Italy by Bernardo d’Alemagna, as Praetorius claims; the organ of the Most Holy Annunciation in Florence, built in 1379, had a pedalboard of twelve pedals called *calculos pro tastando cum pedibus*. It was in this century that Italian cathedrals were definitively equipped with organs *in maiori forma qua fieri posset* (Orvieto, 1373). In the fifteenth century, Italian organ building knew its own artistic directions. The most famous artist of the first half of the century is Matteo da Prato (1395–1465), but unfortunately technical details about his numerous instruments are lacking. The *ripieno*, a sonorous amalgam of numerous pipes tuned in ascending octaves and fifths, assumed those unmistakable and perfect sonorities that still constitute the finest quality of the Italian organ.
The slider chest of positive organs, perhaps for technical difficulties, had not yet been used in the large organ; in Italy the wind chest with pallets was soon introduced, in which the perforated slider was replaced by as many pallets and a rod connected all the pallets of a stop. Although the term “stop” already appears in a Trevisan document of 1436, which records the expense of iron wire *ad infingenda registros et tastos* in the organ of the Cathedral, many decades would pass before the use of regular registration in large organs could be confirmed. The well-known Bernardo d’Alemagna, like perhaps Matteo da Prato, still belonged to the old school that did not know the division of stops in the windchests. Zarlino (1588) praised an ancient organ of suitable size in the Basilica of the Santo in Padua, whose windchest had *alcuno registrato*. But Bernardo’s son, known by the name of Antonio Dilmano, in 1487 transformed the organ of Milan Cathedral, made by father and son, *de antico ad modernum*, and more explicitly in 1495 he transformed into the new style *cum registri* an instrument in Feltre. In this period and in the sixteenth century, among the Italian organ builders stand out Lorenzo di Giacomo (S. Petronio in Bologna, 1471, one of the few ancient instruments still extant), Domenico di Lorenzo (St. Peter’s in the Vatican, 1496), G. Battista Fachetti (S. Lorenzo in Genoa, 1552), Vincenzo Colombo (S. Marco in Venice, 1558), Luca Biasi (S. Giovanni in Laterano, 1597), and above all the Antegnati family of Brescia. In *Arte organica*, published in 1608, Costanzo Antegnati extolled the artistic merits of his own family; Antonio Barcotto in a treatise of 1652 completed the technical knowledge of the classical Italian organ. It had no innovating tendencies: to the family of the principals forming the *ripieno* in the last decades of the fifteenth century were added only the fifteenth and twelfth flutes, and in the second half of the sixteenth century the *fiffaro* or *voce umana*, a stop based on acoustic tremolo. Instruments with two manuals or with numerous stops of varied timbre, common abroad, were exceptions in Italy. Technically perfected, the organ achieved a tonal balance that favored the development of organ composition and reached its peak in Johann Sebastian Bach. It was the period of the greatest flowering of German organ building, and famous organ builders created important and grand instruments. In Italy there was no parallel evolution at that time, even though foreign organ builders tried to expand the perfect but restricted scheme of the Italian organ. Eugenio Gasparini (1624–1706), a Silesian, the first teacher of Andreas Silbermann, for almost half a century propagated a new technique in the Veneto region. Guglielmo Hermans (1601–83), a Flemish Jesuit lay brother, spread throughout Italy the advanced forms of the northern organ; the Provençal school made its way into Piedmont with Antonio Julian, and perhaps with an anonymous treatise (ms. in the Biblioteca Martini, Bologna), in which the Italian and French organ-building schools of the second half of the seventeenth century are compared. But Italian organ builders did not depart from the national tradition; only in the eighteenth century did Azzolino della Ciaia (1671–1753) in Pisa and Donato del Piano (1698–1785) in Catania build instruments of exceptional size for Italy, and the Venetian school of Pietro Nacchini (1694–1770) and Gaetano Callido (1727–1813) adopted proportions skillfully studied from classical models and foreign technical treatises. Only with the Serassi family of Bergamo did the Italian organ acquire new timbres, especially of the *ance* family; yet in form it did not assimilate the technical characteristics necessary for performing organ compositions by German and French composers.
German Romanticism replaced the characteristic sonorities of the Baroque organ with orchestral timbres. The nineteenth-century organ benefited from many innovations, such as the Barker pneumatic lever, tubular pneumatic action, piston windchests, etc.; these innovations partly determined the true organ sonorities. The French organ also felt the Romantic influence, but it had in Cavaillé-Coll (1811–99) a brilliant artist who knew how to avoid excesses. In Italy, toward the last decades of the nineteenth century, with the spread of the Cecilian movement, the reform of the organ was not limited to the necessary technical updates regarding the number and shape of manuals and pedals, but altered traditional sonorities to follow Romantic ideals. The Englishman William Trice (1847–1918) was the first to introduce into Italy the new manufacturing systems. A gifted artist of refined sensitivity was Carlo Vegezzi-Bossi (1858–1927), who grafted traditional Italian tonal qualities onto the reformed organ.
Toward the first quarter of the present century, a reactionary movement arose in Germany in favor of Baroque sonorities, while the American organ of recent decades, through the brilliant technical innovations of skilled artists like Robert Hope-Jones (1859–1914), spread the new sonorities of high-pressure stops and perfect electric actions. Yet even the best European factories, not least the Italian ones, vied with American products in technical perfection. Modern technology has succeeded in replacing organ pipes with electric circuits; various types of instruments have spread as substitutes for the traditional organ, the best known of which is the Hammond electric organ.
With the introduction of the numbered bass, the organ became the most suitable instrument for realizing the figured bass in sacred compositions. It then performed a similar function in concerted sacred music with instruments, even when the orchestra assumed considerable importance, as in the so-called Viennese classics (Haydn, Mozart, etc.). In figured music, the organ is today often entrusted with an obbligato part with prominent tasks. A particular development was the organ accompaniment of Gregorian chant, which in modern times is often a practical necessity and increasingly enhances the importance of the organ as a support for popular song.
Modern technical resources, which facilitate the connection of multiple organs in a single console, even when they are located at a considerable distance from one another, can be usefully exploited, provided that the mistake is not made of considering the individual bodies, placed far apart, as a single instrument.
For the use of the organ in churches v.: MUSIC.
ART. – No monumental organs are known in churches prior to the mid-15th century. In the earliest examples, the case lacks ornamentation, and the pipes may be concealed behind doors, usually painted on the exterior with a single scene featuring images of saints or distinct scenes. This decoration of the organ, often entrusted to great artists, was frequent in northern Italy (a famous example being the organ doors by Cosmè Tura, now in the Museo del Duomo in Ferrara), especially in the Veneto and regions artistically connected to Venice; organ doors were painted by Giovanni Bellini, Vittore Carpaccio, Sebastiano del Piombo, Tintoretto, Paolo Veronese, and in Brescia by Romanino and Moretto, even into the late 16th century. In central Italy, by the early 16th century, organs with visible pipes set within an architectural display had come into use: one of the earliest known examples is that of Santa Maria della Scala in Siena, designed by Peruzzi; slightly later is the organ of Arezzo Cathedral, from 1535, the first architectural work by Vasari, conceived as an altarpiece frame and connected to the underlying cantoria.
But especially in the 17th century, with the development of sacred music, the importance of the organ grew, and the lavishness of the Baroque enriched its displays with ever more elaborate ornamentation, cantoria (v.). After Bernini, who in the famous organ of the right transept of Santa Maria del Popolo achieved a new pictorial effect in the contrast between the rigid verticality of the pipes and the movement of the gilded foliage, 17th-century creativity indulged in adorning organs with garlands, scrolls, and statues (Chiesa Nuova); when placed on the counterfaçade, the organ became the central motif of the architectural composition of the entire wall (Santa Maria della Vittoria, Gesù e Maria, etc.).
In the 18th century, the organ of the Maddalena Church is a vivid example of the most extensive Rococo style. 19th-century displays of architectural character are rarer; among these are remembered those of the Gesù in Rome, which coldly repeat 16th-century motifs, and that of the church of the Servites in Rimini, which forms a monumental ensemble with the cantoria supported by caryatids. – See plates XVIII-XIX.
