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69-520: The town was almost completely leveled in an earthquake in the 1960s and as a result contains very little architecture from before this period. The church was built in the nineteenth century on a basic basilica groundplan in a central location within the town. It is dedicated to Saint George, but celebrates on the Dormition of the Virgin. In 2004 a fire which was most likely caused by an unattended oil-lamp gutted

138-590: A Bachelor's degree or higher qualification. Some possess a degree in acoustics, while others enter the discipline via studies in fields such as physics or engineering . Much work in acoustics requires a good grounding in Mathematics and science . Many acoustic scientists work in research and development. Some conduct basic research to advance our knowledge of the perception (e.g. hearing , psychoacoustics or neurophysiology ) of speech , music and noise . Other acoustic scientists advance understanding of how sound

207-562: A definite mathematical structure. The wave equation emerged in a number of contexts, including the propagation of sound in air. In the nineteenth century the major figures of mathematical acoustics were Helmholtz in Germany, who consolidated the field of physiological acoustics, and Lord Rayleigh in England, who combined the previous knowledge with his own copious contributions to the field in his monumental work The Theory of Sound (1877). Also in

276-547: A key element of mating rituals or for marking territories. Art, craft, science and technology have provoked one another to advance the whole, as in many other fields of knowledge. Robert Bruce Lindsay 's "Wheel of Acoustics" is a well accepted overview of the various fields in acoustics. The word "acoustic" is derived from the Greek word ἀκουστικός ( akoustikos ), meaning "of or for hearing, ready to hear" and that from ἀκουστός ( akoustos ), "heard, audible", which in turn derives from

345-400: A result of varying auditory stimulus which can in turn affect the way one thinks, feels, or even behaves. This correlation can be viewed in normal, everyday situations in which listening to an upbeat or uptempo song can cause one's foot to start tapping or a slower song can leave one feeling calm and serene. In a deeper biological look at the phenomenon of psychoacoustics, it was discovered that

414-405: A rock concert. The central stage in the acoustical process is wave propagation. This falls within the domain of physical acoustics. In fluids , sound propagates primarily as a pressure wave . In solids, mechanical waves can take many forms including longitudinal waves , transverse waves and surface waves . Acoustics looks first at the pressure levels and frequencies in the sound wave and how

483-456: A sound wave to or from an electric signal. The most widely used transduction principles are electromagnetism , electrostatics and piezoelectricity . The transducers in most common loudspeakers (e.g. woofers and tweeters ), are electromagnetic devices that generate waves using a suspended diaphragm driven by an electromagnetic voice coil , sending off pressure waves. Electret microphones and condenser microphones employ electrostatics—as

552-407: A string sounds the note C when plucked, a string twice as long will sound a C an octave lower. In one system of musical tuning , the tones in between are then given by 16:9 for D, 8:5 for E, 3:2 for F, 4:3 for G, 6:5 for A, and 16:15 for B, in ascending order. Aristotle (384–322 BC) understood that sound consisted of compressions and rarefactions of air which "falls upon and strikes the air which

621-751: A virtual divide. The iconostasis typically has three openings or sets of doors: the Beautiful Gates or Holy Doors in the center, and the North and South Doors to either side. The Beautiful Gates are sometimes called the Royal Doors , but that name more properly belongs to the central doors connecting the narthex , or porch, to the nave . They remain shut whenever a service is not being held. Modern custom as to when they should be opened during services varies depending upon jurisdiction and local custom. The North and South Doors are often called Deacons' Doors because

690-438: A wave comparable to a water wave extended to three dimensions, which, when interrupted by obstructions, would flow back and break up following waves. He described the ascending seats in ancient theaters as designed to prevent this deterioration of sound and also recommended bronze vessels (echea) of appropriate sizes be placed in theaters to resonate with the fourth, fifth and so on, up to the double octave, in order to resonate with

759-465: A way of echolocation in the caves. In archaeology, acoustic sounds and rituals directly correlate as specific sounds were meant to bring ritual participants closer to a spiritual awakening. Parallels can also be drawn between cave wall paintings and the acoustic properties of the cave; they are both dynamic. Because archaeoacoustics is a fairly new archaeological subject, acoustic sound is still being tested in these prehistoric sites today. Aeroacoustics

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828-405: A π shape, with one large door facing the nave and two smaller doors on the other sides. Twelve piers held chancel slabs of about 1.6 meters in length. The height of the slabs is not known. The chancel barrier was not merely a low parapet (a short wall); remains of colonnettes have been found, suggesting that the barrier carried an architrave on top of the columns. In early churches, including

897-432: 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 while someone working in the field of acoustics technology may be called an acoustical engineer . The application of acoustics is present in almost all aspects of modern society with

966-536: Is a wall of icons and religious paintings, separating the nave from the sanctuary in a church . Iconostasis also refers to a portable icon stand that can be placed anywhere within a church. The iconostasis evolved from the Byzantine templon , a process complete by the 15th century. A direct comparison for the function of the main iconostasis can be made to the layout of the great Temple in Jerusalem . That Temple

1035-503: Is affected as it moves through environments, e.g. underwater acoustics , architectural acoustics or structural acoustics . Other areas of work are listed under subdisciplines below. Acoustic scientists work in government, university and private industry laboratories. Many go on to work in Acoustical Engineering . Some positions, such as Faculty (academic staff) require a Doctor of Philosophy . Archaeoacoustics , also known as

1104-416: Is concerned with noise and vibration caused by railways, road traffic, aircraft, industrial equipment and recreational activities. The main aim of these studies is to reduce levels of environmental noise and vibration. Research work now also has a focus on the positive use of sound in urban environments: soundscapes and tranquility . Musical acoustics is the study of the physics of acoustic instruments;

1173-408: Is defined by ANSI/ASA S1.1-2013 as "(a) Science of sound , including its production, transmission, and effects, including biological and psychological effects. (b) Those qualities of a room that, together, determine its character with respect to auditory effects." The study of acoustics revolves around the generation, propagation and reception of mechanical waves and vibrations. The steps shown in

1242-430: Is how our ears interpret sound. What we experience as "higher pitched" or "lower pitched" sounds are pressure vibrations having a higher or lower number of cycles per second. In a common technique of acoustic measurement, acoustic signals are sampled in time, and then presented in more meaningful forms such as octave bands or time frequency plots. Both of these popular methods are used to analyze sound and better understand

1311-624: Is next to it...", a very good expression of the nature of wave motion. On Things Heard , generally ascribed to Strato of Lampsacus , states that the pitch is related to the frequency of vibrations of the air and to the speed of sound. In about 20 BC, the Roman architect and engineer Vitruvius wrote a treatise on the acoustic properties of theaters including discussion of interference, echoes, and reverberation—the beginnings of architectural acoustics . In Book V of his De architectura ( The Ten Books of Architecture ) Vitruvius describes sound as

1380-416: Is the electronic manipulation of acoustic signals. Applications include: active noise control ; design for hearing aids or cochlear implants ; echo cancellation ; music information retrieval , and perceptual coding (e.g. MP3 or Opus ). Architectural acoustics (also known as building acoustics) involves the scientific understanding of how to achieve good sound within a building. It typically involves

1449-431: Is the scientific study of the hearing and calls of animal calls, as well as how animals are affected by the acoustic and sounds of their habitat. This subdiscipline is concerned with the recording, manipulation and reproduction of audio using electronics. This might include products such as mobile phones , large scale public address systems or virtual reality systems in research laboratories. Environmental acoustics

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1518-413: Is the study of noise generated by air movement, for instance via turbulence, and the movement of sound through the fluid air. This knowledge was applied in the 1920s and '30s to detect aircraft before radar was invented and is applied in acoustical engineering to study how to quieten aircraft . Aeroacoustics is important for understanding how wind musical instruments work. Acoustic signal processing

1587-797: Is used as a cemetery church. The church is on the hill overlooking the town near a spring. The House of the Revolutionary hero Dimitris Plapoutas is very centrally located in the town. Once known as "ο πύργος" (The Tower) because it was the biggest house in the town, the house used to be a tri-level mansion with stables. The upper two levels were destroyed in a 1960s earthquake . Iconostasis Autocephaly recognized by some autocephalous Churches de jure : Autocephaly and canonicity recognized by Constantinople and 3 other autocephalous Churches: Spiritual independence recognized by Georgian Orthodox Church: Semi-Autonomous: In Eastern Christianity , an iconostasis ( Greek : εἰκονοστάσιον )

1656-460: Is usually small, it is still noticeable to the human ear. The smallest sound that a person can hear, known as the threshold of hearing , is nine orders of magnitude smaller than the ambient pressure. The loudness of these disturbances is related to the sound pressure level (SPL) which is measured on a logarithmic scale in decibels. Physicists and acoustic engineers tend to discuss sound pressure levels in terms of frequencies, partly because this

1725-572: The Gothic Revival , particularly in Anglican churches in England . In wooden examples, painted panels were typically waist-high, with a wooden tracery section above allowing a view through, and then a large carved beam supporting a rood cross crucifix , often life-size, above that. Larger churches had stone screens, which might impede virtually all view by the congregation. Acoustics Acoustics

1794-617: The Hagia Sophia ("Great Church") in Constantinople , the altar, at least in large churches, was under a ciborium ( ciborion : κιβώριον in Greek), usually a structure with four columns and a domed canopy. This had curtains on rods on all four sides, which were closed for sections of the liturgy, as is still performed in the Coptic and Armenian churches, a comparison with the biblical Veil of

1863-613: The Holy of Holies ; rather, it is seen as bringing them together. The iconostasis is the link between heaven (the Holy of Holies) and the nave (the Holy Place). Therefore, everything is symbolic upon the iconostasis. The icons of Christ, the Theotokos, and various saints and feasts are there because Christ, the Theotokos, the saints etc., are said to lead and guide followers into the Holy of Holies. Therefore,

1932-499: The Romanian tradition , on the day of the consecration of the altar in the church, the laity, including women, were permitted to enter and venerate the altar until the beginning of the Vespers of Consecration. These guidelines were developed over the course of many centuries, with both theologically symbolic and practical reasons for them. The iconostasis does not separate the nave from

2001-399: The altar , east of the nave. The sanctuary is usually one to three steps higher than the nave. The iconostasis does not sit directly on the edge of the sanctuary but is usually set a few feet back from the edge of the top step. This forms a walkway in front of the iconostasis for the clergy, called a soleas . In the very center of the soleas is an extension (or thrust ), often rounded, called

2070-425: The ambon , on which the deacon will stand to give litanies during the services. The iconostasis, though often tall, rarely touches the ceiling. Acoustically , this permits the ekphoneses (liturgical exclamations) of the clergy to be heard clearly by the faithful. In small, modern churches the iconostasis may be completely absent: in such cases it is replaced by a few small icons on analogia (lecterns), forming

2139-688: The audio signal processing used in electronic music; the computer analysis of music and composition, and the perception and cognitive neuroscience of music . The goal this acoustics sub-discipline is to reduce the impact of unwanted sound. Scope of noise studies includes the generation, propagation, and impact on structures, objects, and people. Noise research investigates the impact of noise on humans and animals to include work in definitions, abatement, transportation noise, hearing protection, Jet and rocket noise, building system noise and vibration, atmospheric sound propagation, soundscapes , and low-frequency sound. Many studies have been conducted to identify

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2208-562: The deacons use them frequently. Icons of sainted deacons are often depicted on these doors (particularly St. Stephen the Protomartyr and St. Ephrem the Syrian ). Alternatively, they may be called Angels' Doors , and the Archangels Michael and Gabriel are often depicted there. The South Door is typically the "entrance" door, and Michael is depicted there because he is the "Defender";

2277-444: The harmonic overtone series on a string. He is reputed to have observed that when the lengths of vibrating strings are expressible as ratios of integers (e.g. 2 to 3, 3 to 4), the tones produced will be harmonious, and the smaller the integers the more harmonious the sounds. For example, a string of a certain length would sound particularly harmonious with a string of twice the length (other factors being equal). In modern parlance, if

2346-555: The speed of sound in air were carried out successfully between 1630 and 1680 by a number of investigators, prominently Mersenne. Meanwhile, Newton (1642–1727) derived the relationship for wave velocity in solids, a cornerstone of physical acoustics ( Principia , 1687). Substantial progress in acoustics, resting on firmer mathematical and physical concepts, was made during the eighteenth century by Euler (1707–1783), Lagrange (1736–1813), and d'Alembert (1717–1783). During this era, continuum physics, or field theory, began to receive

2415-476: The "side doors". There are some exceptions where both the side doors depict Archangel Michael. The most notable exception is of the church of Saint George (Aghios Georgios) inside the Ecumenical Patriarchate of Constantinople (in today's Istanbul). In many monastery churches and chapels (though often not in the katholikon , the monastery's main church) one may find iconostases with only two doors:

2484-415: The 19th century, Wheatstone, Ohm, and Henry developed the analogy between electricity and acoustics. The twentieth century saw a burgeoning of technological applications of the large body of scientific knowledge that was by then in place. The first such application was Sabine 's groundbreaking work in architectural acoustics, and many others followed. Underwater acoustics was used for detecting submarines in

2553-556: The 6th, 7th, and 8th centuries, except in Cappadocia . The invention of the solid icon screen is ascribed to Saint Basil the Great . As late as the 10th century, a simple wooden chancel barrier separated the apse from the nave in the rock-cut churches in Derinkuyu , although by the late 11th century, the templon had become standard. This may have been because of the veneration and imitation of

2622-597: The Beautiful Gates. If the cross bears an iconographic depiction of Christ Crucified, it is often flanked by icons of the Theotokos and St. John the Evangelist standing at the foot of the cross. There are rules regarding who may enter or leave the sanctuary (altar), and by which door. Neither the Beautiful Gates (Holy/Royal Doors – central doors) nor the space between them and the altar table may be used by laity under any circumstances, although infants are either carried into

2691-639: The Great Church Hagia Sophia in Constantinople, though the columnar form of chancel barrier does predate Hagia Sophia. The rood screens or pulpita that most large European Roman Catholic churches and cathedrals had acquired by late medieval times occupied a similar position between chancel and nave but served a different function. The choir was usually east of the screen. Many survive, often most completely in Scandinavia , and more were built in

2760-732: The Greek tradition only include the bottom ("Sovereign") tier, and on occasion a second tier of smaller icons, usually depicting either the Great Feasts or the Apostles (with an icon of the Mystical Supper, or occasionally the Hospitality of Abraham) above the Beautiful Gates. When the Iconostasis does not reach all the way to the ceiling, it is often surmounted by a central cross, centered directly above

2829-594: The Holy Doors and the North Door. These churches are used for simpler monastic observances when only a hieromonk would be serving alone. A number of guidelines or rubrics govern which icons are on which parts of the iconostasis, although there is some room for variation. In its fullest Slavic development, it comprised five tiers of icons: It is also not uncommon to find an icon of the Mystical Supper , which depicts

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2898-680: The Last Supper, and by extension the Communion of Saints in the Kingdom of God , somewhere above the Beautiful Gates. The Sovereign (bottom) tier is found in all iconostases, but other tiers are somewhat optional. In general, preference is given to the Deisis or the Feasts tiers if only some of them can be included, and only the largest and most elaborate iconostases have all five tiers. Many modern iconostases in

2967-586: The North Door is the "exit", and Gabriel is depicted here because he is the "Messenger" of God. (In the Greek and Antiochian liturgical tradition, the Archangel Michael is usually stationed on the north (i.e. "exit") door, and Gabriel on the south (i.e. "entrance") door, and that it is far more common in modern times to see the Archangels than the Deacons on these doors). These doors may also be casually referred to as

3036-607: The Temple was intended. The small domed structures, usually with red curtains, that are often shown near the writing saint in early Evangelist portraits , especially in the East, represent a ciborium, as do the structures surrounding many manuscript portraits of medieval rulers. As the iconostasis grew, the ciborium declined, although some late examples, by now invisible to the congregation, were produced. The templon gradually replaced all other forms of chancel barriers in Byzantine churches in

3105-461: The above diagram can be found in any acoustical event or process. There are many kinds of cause, both natural and volitional. There are many kinds of transduction process that convert energy from some other form into sonic energy, producing a sound wave. There is one fundamental equation that describes sound wave propagation, the acoustic wave equation , but the phenomena that emerge from it are varied and often complex. The wave carries energy throughout

3174-594: The acoustic phenomenon. The entire spectrum can be divided into three sections: audio, ultrasonic, and infrasonic. The audio range falls between 20 Hz and 20,000 Hz. This range is important because its frequencies can be detected by the human ear. This range has a number of applications, including speech communication and music. The ultrasonic range refers to the very high frequencies: 20,000 Hz and higher. This range has shorter wavelengths which allow better resolution in imaging technologies. Medical applications such as ultrasonography and elastography rely on

3243-463: The altar portion behind the iconostasis. However, one will see women serving behind the iconostasis at female monasteries . The word iconostasis comes from the Greek εἰκονοστάσι(-ον) ( eikonostási(-on) ), still in common use in Greece and Cyprus), which means ' icon stand ' . The nave is the main body of the church where most of the worshippers stand, and the sanctuary is the area around

3312-401: The altar through them in the " churching " rite if they are boys, or if they are girls, the infant is simply presented at the doors. Bishops may enter through the Beautiful Gates at any time; priests and deacons may do so only at specific times during the services when the gates are open (but during Bright Week they always enter and exit through them). All others enter the sanctuary through

3381-429: The archaeology of sound, is one of the only ways to experience the past with senses other than our eyes. Archaeoacoustics is studied by testing the acoustic properties of prehistoric sites, including caves. Iegor Rezkinoff, a sound archaeologist, studies the acoustic properties of caves through natural sounds like humming and whistling. Archaeological theories of acoustics are focused around ritualistic purposes as well as

3450-493: The central nervous system is activated by basic acoustical characteristics of music. By observing how the central nervous system, which includes the brain and spine, is influenced by acoustics, the pathway in which acoustic affects the mind, and essentially the body, is evident. Acousticians study the production, processing and perception of speech. Speech recognition and Speech synthesis are two important areas of speech processing using computers. The subject also overlaps with

3519-411: The church destroying the exquisitely worked carved wooden iconostasis which had been granted as a gift by King Ludwig I of Bavaria , father of King Otto the first King of the newly established Independent Greek State. Work has commenced under the supervision of the local Ephorate of Byzantine Antiquities to repair the damage and re-roof the structure. The church is on the western edge of the town and

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3588-438: The complete laws of vibrating strings (completing what Pythagoras and Pythagoreans had started 2000 years earlier). Galileo wrote "Waves are produced by the vibrations of a sonorous body, which spread through the air, bringing to the tympanum of the ear a stimulus which the mind interprets as sound", a remarkable statement that points to the beginnings of physiological and psychological acoustics. Experimental measurements of

3657-536: The disciplines of physics, physiology , psychology , and linguistics . Structural acoustics is the study of motions and interactions of mechanical systems with their environments and the methods of their measurement, analysis, and control. There are several sub-disciplines found within this regime: Applications might include: ground vibrations from railways; vibration isolation to reduce vibration in operating theatres; studying how vibration can damage health ( vibration white finger ); vibration control to protect

3726-456: The first World War. Sound recording and the telephone played important roles in a global transformation of society. Sound measurement and analysis reached new levels of accuracy and sophistication through the use of electronics and computing. The ultrasonic frequency range enabled wholly new kinds of application in medicine and industry. New kinds of transducers (generators and receivers of acoustic energy) were invented and put to use. Acoustics

3795-586: The more desirable, harmonious notes. During the Islamic golden age , Abū Rayhān al-Bīrūnī (973–1048) is believed to have postulated that the speed of sound was much slower than the speed of light. The physical understanding of acoustical processes advanced rapidly during and after the Scientific Revolution . Mainly Galileo Galilei (1564–1642) but also Marin Mersenne (1588–1648), independently, discovered

3864-467: The most obvious being the audio and noise control industries. Hearing is one of the most crucial means of survival in the animal world and speech is one of the most distinctive characteristics of human development and culture. Accordingly, the science of acoustics spreads across many facets of human society—music, medicine, architecture, industrial production, warfare and more. Likewise, animal species such as songbirds and frogs use sound and hearing as

3933-507: The personages on the icons upon the iconostasis guide followers into heaven, and therefore the iconostasis is said to connect, not separate. Icons are seen as windows and bridges to heaven. Therefore, in a sense the iconostasis represents Christ, who is the connection, the door, between both realms. The perfect explanation for the iconostasis, and its uniting purpose, is seen in Hebrews 10:19–20, "Therefore, brethren, since we have confidence to enter

4002-406: The propagating medium. Eventually this energy is transduced again into other forms, in ways that again may be natural and/or volitionally contrived. The final effect may be purely physical or it may reach far into the biological or volitional domains. The five basic steps are found equally well whether we are talking about an earthquake , a submarine using sonar to locate its foe, or a band playing in

4071-435: The relationship between acoustics and cognition , or more commonly known as psychoacoustics , in which what one hears is a combination of perception and biological aspects. The information intercepted by the passage of sound waves through the ear is understood and interpreted through the brain, emphasizing the connection between the mind and acoustics. Psychological changes have been seen as brain waves slow down or speed up as

4140-500: The sanctuary by the blood of Jesus , by the new and living way which he opened for us through the curtain, that is through his flesh.". Archaeological evidence from the St. John of Stoudios monastery in Constantinople suggests that the iconostasis evolved from the early templon . A basilica dedicated to John the Baptist was built in 463 AD. In it the chancel barrier surrounded the altar in

4209-486: The side doors. In a convent , only the abbess and elder nuns are permitted to enter the sanctuary (altar), and they may only enter through the side doors. The abbess may enter at any time, but the other nuns need a blessing to enter. Male members of the laity who are usually allowed to enter the sanctuary include those involved in the running of the particular church, i.e., cantors and choristers , altar servers /acolytes, church keepers and vestrymen , etc. In

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4278-444: The sound wave strikes the microphone's diaphragm, it moves and induces a voltage change. The ultrasonic systems used in medical ultrasonography employ piezoelectric transducers. These are made from special ceramics in which mechanical vibrations and electrical fields are interlinked through a property of the material itself. An acoustician is an expert in the science of sound. There are many types of acoustician, but they usually have

4347-468: The study of speech intelligibility, speech privacy, music quality, and vibration reduction in the built environment. Commonly studied environments are hospitals, classrooms, dwellings, performance venues, recording and broadcasting studios. Focus considerations include room acoustics, airborne and impact transmission in building structures, airborne and structure-borne noise control, noise control of building systems and electroacoustic systems. Bioacoustics

4416-456: The time varying pressure level and frequency profiles which give a specific acoustic signal its defining character. A transducer is a device for converting one form of energy into another. In an electroacoustic context, this means converting sound energy into electrical energy (or vice versa). Electroacoustic transducers include loudspeakers , microphones , particle velocity sensors, hydrophones and sonar projectors. These devices convert

4485-627: The two main parts can be seen carried forward in Christian churches and is still most demonstratively present in Eastern Orthodox churches where the iconostasis divides the altar, the Holy of Holies where the Eucharist is performed – the manifestation of the New Covenant  – from the larger portion of the church accessible to the faithful. In the Eastern Orthodox tradition, usually only men can enter

4554-420: The ultrasonic frequency range. On the other end of the spectrum, the lowest frequencies are known as the infrasonic range. These frequencies can be used to study geological phenomena such as earthquakes. Analytic instruments such as the spectrum analyzer facilitate visualization and measurement of acoustic signals and their properties. The spectrogram produced by such an instrument is a graphical display of

4623-500: The verb ἀκούω( akouo ), "I hear". The Latin synonym is "sonic", after which the term sonics used to be a synonym for acoustics and later a branch of acoustics. Frequencies above and below the audible range are called " ultrasonic " and " infrasonic ", respectively. In the 6th century BC, the ancient Greek philosopher Pythagoras wanted to know why some combinations of musical sounds seemed more beautiful than others, and he found answers in terms of numerical ratios representing

4692-416: The wave interacts with the environment. This interaction can be described as either a diffraction , interference or a reflection or a mix of the three. If several media are present, a refraction can also occur. Transduction processes are also of special importance to acoustics. In fluids such as air and water, sound waves propagate as disturbances in the ambient pressure level. While this disturbance

4761-552: Was designed with three parts. The holiest and inner-most portion was that where the Ark of the Covenant was kept. This portion, the Holy of Holies , was separated from the second larger part of the building's interior by a curtain, the "veil of the temple" . Only the High Priest was allowed to enter the Holy of Holies. The third part was the entrance court. This architectural tradition for

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