(Fr. orgue hydraulique; Ger. Wasserorgel; Lat. organum hydraulicum).
A kind of automatic organ without bellows. It is blown and sounded by air compressed directly by water that is activated by natural forces (e.g. by a waterfall). Water organs play without human intervention once they are set in action. Ancient and modern writers have frequently confused them with the Greco-Roman Hydraulis, a type of pneumatic organ in which air was supplied by hand-operated air pumps and water was used in a device to steady the wind-pressure. Unlike the steam organ (seeCalliope (ii)), which did employ ‘wet’ air, no water ever coursed through the musical pipes of the water organ. Apart from the method of blowing, the water organ is similar to the Barrel organ, having a pinned barrel carrying the musical programme, a windchest and pipework.
Water organs were described in the texts of Ctesibius (3rd century bce), Philo of Byzantium (3rd century bce) and Hero of Alexandria (c62 ce). Like the water clocks (clepsydra) of Plato's time, they were not regarded as playthings but might have had a particular significance in Greek philosophy, which made use of models and simulacra of this type. Hydraulically blown organ pipes were used to imitate birdsong, as well as to produce the awe-inspiring sound emitted by Memnon's statue at Thebes. For the latter, solar heat was used to syphon water from one closed tank into another, thereby producing compressed air for sounding the pipes.
Arab and Byzantine engineers developed, among other pieces, an automatic water organ (described by the Banū Mūsā in their 9th-century treatise; see Farmer, 1931), and a ‘musical tree’ at the palace of Khalif al-Muqtadir (ruled 908–32). By the end of the 13th century hydraulic automata had reached Italy and the rest of Western Europe. During the Renaissance water organs again acquired magical and metaphysical connotations among followers of the hermetic and esoteric sciences. Organs were placed in gardens, grottoes and conservatories of royal palaces and the mansions of rich patricians to delight onlookers not only with music but also with displays of automata – dancing figurines, wing-flapping birds and hammering cyclopes – all operated by projections on the musical cylinder (see fig.1). Other types of water organ were played out of sight and were used to simulate musical instruments apparently being played by statues in mythological scenes such as ‘Orpheus playing the viol’, ‘The contest between Apollo and Marsyas’ and ‘Apollo and the nine Muses’.
The most famous water organ of the 16th century was at the Villa d'Este in Tivoli (fig.2). Built about 1569–72 by Lucha Clericho (Luc de Clerc; completed by Claude Venard), it stood about six metres high under an arch, and was fed by a magnificent waterfall; it was described by Mario Cartaro in 1575 as playing ‘madrigals and many other things’. It was also provided with a keyboard. G.M. Zappi (Annalie memorie de Tivoli, 1576) wrote: ‘When somebody gives the order to play, at first one hears trumpets which play awhile and then there is a consonnance …. Countless gentlemen could not believe that this organ played by itself, according to the registers, with water, but they rather thought that there was somebody inside’. Besides automatically playing at least three pieces of music, it is now known that the organ was also provided with a keyboard. Other Italian gardens with water organs were at Pratolino, near Florence (c1580), Isola de Belvedere, Ferrara (before 1599), Palazzo del Quirinale, Rome (built by Luca Biagi in 1598, restored 1990), Villa Aldobrandini, Frascati (1620), one of the Royal Palaces at Naples (1746), Villa Doria Pamphili, Rome (1758–9). Of these only the one at the Palazzo del Quirinale has survived. Kircher’s illustration in Musurgia universalis (1650; see fig.1), long thought to be a fanciful representation of a hypothetical possibility, has been found to be accurate in every detail when compared to the organ grotto at the Quirinale, except that it was reversed left to right. There are still traces of the instrument at the Villa d’Este but the mineral-rich water of the river which cascades through the organ grotto has caused accretions which have hidden most of the evidence from view.
In the early 17th century water organs were built in England; Cornelius Drebbel built one for King James I (see Harstoffer, 1651), and Salomon de Caus built several at Richmond while in the service of Prince Henry. There was one in Bagnigge Vale, London, the summer home of Nell Gwynn (1650–87), and Henry Winstanley (1644–1703), the designer of the Eddystone Lighthouse, is thought to have built one at his home in Saffron Walden, Essex. After the marriage of Princess Elizabeth to the Elector Palatine Prince Friedrich V, de Caus laid out for them the gardens at Heidelberg Castle which became famous for their beautiful and intricate waterworks. A water organ survives in the gardens at Heilbronn, Württemberg, and parts of one at the Wilhelmshöhe gardens in Kassel. The brothers Francini constructed waterworks and organs at Saint Germain-en-Laye and Versailles, which reached new heights of splendour and extravagance.
By the end of the 17th century, however, interest in water organs had waned. As their upkeep was costly they were left to decay and were soon forgotten; by 1920 not one survived (the so-called water organ at Hellbrunn Castle, Salzburg, is a pneumatic organ driven by hydraulically operated bellows). Their mechanism was subsequently misunderstood until the Dutch engineer Van Dijk pointed out in 1954 that the method of air supply to the water organ was the same as that used in forges and smelting works in the 16th and 17th centuries. The most important factor is the natural characteristic of water, when drawn by gravity into an outlet, to suck air in with it. In fig.3 air is drawn through a small pipe placed in a larger vertical pipe, which takes water from a stream, pond or stabilizing reservoir. Both water and air arrive together in the camera aeolis (wind chamber) which is situated a considerable distance below the head of the water. The longer the vertical pipe, the more forceful the suction will be and the greater the volume of air sucked in. Here water and air separate and the compressed air is driven into a wind-trunk on top of the camera aeolis, to blow the organ pipes. The two perforated ‘splash plates’ or ‘diaphragms’ prevent the water spray getting into the organ pipes. The water, having been separated from the air, leaves the camera aeolis at the same rate as it enters it and is used to drive a water wheel, which in turn drives the musical cylinder and the movements attached. To start the organ, the tap above the entry pipe has to be turned on and, given a continuous flow of water, the organ plays until the tap is closed again. Many water organs had simple wind-pressure regulating devices. At the Palazzo del Quirinale, the water flows from a hilltop spring (once abundant, now only sufficient to play the organ for about 30 minutes at a time), coursing through the palace itself into a stabilizing ‘room’ some 18 metres above the camera aeolis in the organ grotto. This drop provides sufficient wind to power the restored six-stop instrument.
Among Renaissance writers on the water organ, Salomon de Caus was particularly informative. His book of 1615 includes a short treatise on making water organs, advice on tuning and registration, and many fine engravings showing the instruments, their mechanisms and scenes in which they were used. It also includes an example of suitable music for water organ, the madrigal Chi farà fed' al cielo by Alessandro Striggio (i), arranged by Peter Philips.
G.Agricola: De re metallica (Basle, 1556); Eng. trans., 1950
T.Nash: The Unfortunate Traveller (London, 1594/R)
G.B.della Porta: Pneumaticorum: libri tres (Naples, 1601)
S. deCaus: Les raisons des forces mouvantes (Frankfurt, 1615, 2/1624) [basis of part of I. de Caus: Nouvelle invention de lever de l'eau (London, 1644; Eng. trans., 1659)]