Melanie Spiller and Coloratura Consulting

Copyright 2020 Melanie Spiller. All rights reserved.

Instrument Biography: The Hydraulis or Water Organ

Melanie Spiller and Coloratura Consulting

Also orgue hydraulique (French) and Wasserorgel (German), hydraulicon, hydraulis, hydraulus. Note: There’s another instrument also called a water organ that plays using air compressed by moving water, such as by a waterfall or a stream. Because they play without human intervention, since ancient Greek times, those water organs have been associated with magic and mystery. They were often built into secret grottoes in ornamental gardens. In the 16 th and 17 th centuries, and were familiar playthings in princes’ palaces. The vogue passed. None survived. This is the tale of another sort of water organ, the predecessor of the pipe organ. The hydraulis is an ancient pneumatic organ in which water controlled the wind pressure through the pipes. It was an important instrument of later classical antiquity, and is the direct ancestor of the modern pipe organ. The hydraulis was the world’s first keyboard instrument. About 250 BCE, an engineer called Ctesibius was noodling around in his garage (just kidding. They didn’t have garages or noodles). He invented useful pneumatic tools that used water to power them, including a kind of mechanical bird that whistled. He tripped over this clever idea to make a keyboard, attach it to some pipes and a lever or two, and pass water through a chamber. Music in the west was forever changed. There are mentions of this instrument in the Old Testament. Genesis (4:21 and 19:14) mentions that an adrabolin was played, which is another word for hydraulis. An early chronicler, Simeon ben Lakish (d. 275 BCE) declared that the ugab was the same as the irdabilis, which was the hydraulis. He’d been a circus performer in his youth and was probably quite familiar with the instrument. You see, in ancient Rome, the hydraulis was often played in with brass instruments, like the cornu and the tuba, in arenas to accompany chariot races and gladiatorial contests, and at the circus.

Hydraulis History

The hydraulis dates back to Ctesibius of Alexandria (fl. 285-222 BCE), who is credited with inventing it. He discovered that water could affect the air pressure in a tube and this is the same system on which modern pneumatics are based. It looks like Ctesibius’ interest in the hydraulis had more to do with making music than with lifting things up, although he did invent a few other water-powered things of a more practical nature. His organ also used the principles of the panpipe, involving multiple pipes, most shaped like a flue, which were the precursors of the recorder’s fipple. The instrument had its heyday during the Roman Empire. The famous orator, politician, and lawyer Cicero (106-43BCE) proclaimed himself a great lover of water-organ music. Suetonius (c.69-122 CE) wrote (in “Life of the Roman Caesars”) that near the end of his life, Nero (38-68 CE) celebrated victories by playing the hydraulis, the choraulos (flute), and the utricularium (bagpipe). In the year 90 BCE, a hydraulis player was described as a sensational success in Delphi during a time when Hellenistic musical and theatrical influences were increasing in southern countries such as Rome. In Israel, the same instrument was called the magrephah. Descriptions are fragmentary and vague, but scholars think the instrument was used during temple services to illustrate the vengeful actions of an angry God. The instrument in its ancient form didn’t survive antiquity. About 1000 years after Ctesibius, a hydraulis was brought from Byzantium to France as a novelty, but they omitted the most important part of the instrument, the water compressor (in the lower chamber).

Hydraulis Structure

Clay reliefs in the Musee Lavigerie de Saint-Louis at Carthage depict the hydraulis as a narrow box that stands about waist high, flanked by pumps on either side that were worked by two additional men. The pipes stand above the box in vertical rows, like those of a modern organ. The player pushes and pulls on keys, opening the pipes to make a sound and closing them to silence them. It’s not clear whether there were as many notes as there were pipes, and some sources imply that multiple pipes could be opened for the same note, making a louder sound. Two assistants pumped air into a funnel-shaped container called the pnigeus, that stood in the lower chamber, which was a cylinder half-filled with water. The water, like the weights used in later organs, held the air under constant pressure. When the pumped-in air raised the level of the water, the water passed into an upper chamber through a tube. The upper chamber, called the arcula, was furnished with flue pipes (like a bank of pan pipes). In later instruments, the bank of pipes could be changed for those in another mode, like the registers or manuals in a modern organ. To make the instrument sound, the player pressed the keys, which worked like simple levers—when a key was pressed, the far end opened the end of the pipe so that air could pass through and make a sound. Because of the shape of the resonant upper chamber and the amplifying nature of water, the sound that came out was quite loud. Here is what the inner works looked like in its crudest form Inside, the instrument looked roughly like two similarly sized boxes stacked on top of each other. The inverted funnel in the lower chamber stood on legs and its narrow end extended upward into the upper chamber. An air pipe outfitted with pumping levers passed through the outer wall of the lower box and allowed air into the funnel, which kept the water level lower inside the funnel than outside when the levers were actively pumped. The arcula was an empty chamber and acted as the resonator. The pipes protruding from the top of the arcula allowed air to escape and pass through a narrowed area (like a fipple) and make a sound. A diaphragm prevented water from getting into the upper pipes. Here’s what a fancy one with a keyboard looked like: In describing the water organ of Archimedes, Tertullian mentions many of its details, such as “limbs, parts, bands, passages for the notes, outlets for the sounds, combinations for the harmony, and the array of its pipes” but he doesn’t refer to the reeds (tongues) of the pipes, which were surely quite conspicuous. Other ancient writers don’t mention the pipes either. Ancient Israeli versions are described as being a square cubit in size and having ten pipe holes. Listeners said that they could emit 100 different sounds. Its sound is characterized as voluminous and noisy, said to be so loud that the players had to plug their ears (like going to a rock concert, eh?). The main drawback (beside the noise) was that it required precision engineering and it was prone to corrosion and needed constant maintenance. The pipes were bronze and graded in length like panpipes. Originally, there was a single row of pipes, but in the 3 rd century CE, it was built with four, six, and even eight ranks of pipes. It’s thought that the hydraulis could only be played in six modes: hyperlydian, hyperiastian (like the modern key of G, with one sharp), lydian, phrygian, hypolydian, and hypophrygian. By 200 CE, the water tank had been eliminated in favor of a windbag inflated by bellows and compressed air and the modern organ was born. Note: The panpipe (a series of end-blown flutes attached to one another) is an ancestor of the organ, as it used pipes of various lengths and the effect of blowing air across or through them. It was probably first developed in China, although South America seems to have invented them independently.


“Musical Instruments; Their History in Western Culture from the Stone Age to the Present Day,” by Karl Geiringer translated by Bernard Miall. George Allen & Unwin LTD, London, 1949. “Musical Instruments of the World; An Illustrated Encyclopedia.” Sterling Publishing Co., Inc, New York, 1997. “Music in Ancient Israel,” by Alfred Sendrey. Philosophical Library, New York, 1969. “The Norton/Grove Concise Encyclopedia of Music,” edited by Stanley Sadie. W.W. Norton and Company, New York, 1994. The Encyclopedia of Music; Musical Instruments and the Art of Music-Making,” by Max Wade-Matthews and Wendy Thompson. Annes Publishing, Leicestershire, 2012. “The Concise Oxford History of Music,” by Gerald Abraham. Oxford University Press, Oxford, 1979. “Harvard Concise Dictionary of Music,” by Don Michael Randel. Belknap Press, Cambridge, 1978. “Music in the Middle Ages,” by Gustave Reese. W.W. Norton & Co., New York, 1940. “The History of Musical Instruments,” by Curt Sachs. Dover Publications, Minneola, 2006. “Music in Ancient Greece & Rome,” by John G. Landels. Routledge, London, 1999.