The Ear of Dionysius () is a

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

cave carved out of the Temenites hill in the city of

Syracuse Syracuse most commonly refers to: * Syracuse, Sicily, Italy; in the province of Syracuse * Syracuse, New York, USA; in the Syracuse metropolitan area Syracuse may also refer to: Places * Syracuse railway station (disambiguation) Italy * Provi ...

, on the island of

Sicily Sicily (Italian language, Italian and ), officially the Sicilian Region (), is an island in the central Mediterranean Sea, south of the Italian Peninsula in continental Europe and is one of the 20 regions of Italy, regions of Italy. With 4. ...

Italy Italy, officially the Italian Republic, is a country in Southern Europe, Southern and Western Europe, Western Europe. It consists of Italian Peninsula, a peninsula that extends into the Mediterranean Sea, with the Alps on its northern land b ...

. Its name, given by the painter Michelangelo da Caravaggio, comes from its similarity in shape to the human ear. The name is also linked to echoes in the cave.

Geology

The Ear of Dionysius was most likely formed out of an old limestone

quarry A quarry is a type of open-pit mining, open-pit mine in which dimension stone, rock (geology), rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some juri ...

. It is 23 metres high and extends 65 metres back into the cliff. Horizontally, it bends in an approximate "S" shape; vertically it is tapered at the top like a teardrop. Because of its shape, the Ear has extremely good

acoustics Acoustics is a branch of physics that deals with the study of mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound. A scientist who works in the field of acoustics is an acoustician ...

, making even a small sound

resonate Resonance is a phenomenon that occurs when an object or system is subjected to an external force or vibration whose frequency matches a resonant frequency (or resonance frequency) of the system, defined as a frequency that generates a maximu ...

throughout the cave.

Purpose

This cave was dug in Greek/Roman times to provide water storage for Syracuse. A narrow tunnel was dug first. This tunnel was widened by digging down and sideways afterwards, giving the cave its unusual shape. The small narrow tunnel is still visible on the top of this artificial cave. An earthquake struck this area causing damage, and the cave became unusable for water storage afterwards. The cave was named after

Dionysius I of Syracuse Dionysius I or Dionysius the Elder ( 432 – 367 BC) was a Greek tyrant of Syracuse, Sicily. He conquered several cities in Sicily and southern Italy, opposed Carthage's influence in Sicily and made Syracuse the most powerful of the Western ...

who used the cave as a prison, and would listen to hear what his prisoners were saying about him through the echoes in the cave.

History

The name of the cave was coined in 1608 by the painter

Caravaggio Michelangelo Merisi da Caravaggio (also Michele Angelo Merigi or Amerighi da Caravaggio; 29 September 1571 – 18 July 1610), known mononymously as Caravaggio, was an Italian painter active in Rome for most of his artistic life. During the fina ...

, who was shown the grotto by the mathematician, antiquarian and archaeologist

Vincenzo Mirabella Vincenzo Mirabella Alagona (Syracuse, Sicily 1570 - Modica, 1624) was an Italian historian, archaeologist and architect, best known for his work ''Plans of Ancient Syracuse''. Family life Vincenzo Mirabella, son of Michele Mirabella and Giovann ...

. It refers to the tyrant

. According to legend, Dionysius used the cave as a prison for political dissidents, and by means of the perfect acoustics eavesdropped on the plans and secrets of his captives. Another legend claims that Dionysius carved the cave in its shape so that it would amplify the screams of prisoners being tortured in it. The sound-focusing effect can no longer be heard because access to the focal point is no longer possible. The visitors of the cave can however still hear the echo while they are in the Ear of Dionysius. Because of its reputation for acoustic flawlessness, the Ear of Dionysius has also come to refer to a type of

ear trumpet An ear trumpet is a tubular or funnel-shaped device which collects sound waves and leads them into the ear. They are used as hearing aids, resulting in a strengthening of the sound energy impact to the eardrum and thus improved hearing for a deaf ...

that has a flexible tube. The term 'Ear of Dionysius' can also refer to surveillance, specifically for political gain.

In popular culture

The cave is featured as the location of the tomb of

Archimedes Archimedes of Syracuse ( ; ) was an Ancient Greece, Ancient Greek Greek mathematics, mathematician, physicist, engineer, astronomer, and Invention, inventor from the ancient city of Syracuse, Sicily, Syracuse in History of Greek and Hellenis ...

in the 2023 film ''

Indiana Jones and the Dial of Destiny ''Indiana Jones and the Dial of Destiny'' is a 2023 American action-adventure film directed by James Mangold and written by Mangold, David Koepp, Jez Butterworth, Jez and John-Henry Butterworth. It is the fifth and final installment in Indiana_ ...

''.

Notes

External links