Thirteenth-century physics intuited sound self-amplification through reflection.

Evidence

The echo is, to some extent, an original sound, and therein is the magic and charm of it. It is not merely a repetition of what was worth repeating in the bell, but partly the voice of the wood. — Gordon Hempton, John Grossmann, One Square Inch of Silence- One Man’s…, 927 (#expands, via linked claim)

The time it takes for an echo to return from a wall at a known distance could be used to determine the speed of sound. Why didn’t the best scientific minds in the last two thousand years determine the speed of sound using echoes? One problem was the accurate measurement of short intervals of time. But for centuries, it wasn’t clear what actually happened when sound reflected from a surface. Did the surface vibrate in order to send the sound back? Was there a time delay with the sound held at the wall for an interval of time? — Eric J. Heller, Why You Hear What You Hear- An…, 151 (#expands, via linked claim)

Categorization

• XREF: connects to: A thirteenth-century Arab scholar first explained source-loading amplification.; Conceptual confusion about sound reflection delayed its speed measurement for centuries — Eric J. Heller, Why You Hear What You Hear- An…, 151; Nearby reflecting surfaces constructively pile up wave reflections to amplify sound (+1 more)

Related

• A thirteenth-century Arab scholar first explained source-loading amplification. (similarity 0.85)
• Conceptual confusion about sound reflection delayed its speed measurement for centuries (similarity 0.85)
• An echo is partly an original sound from the reflecting material (similarity 0.84)
• Echoes rearrange spectral energy without changing its total (similarity 0.82)
• Mersenne first measured sound speed via echoes and speech timing (similarity 0.80)
• Reflections cannot introduce frequencies not present in the original sound (similarity 0.79)
• Every echo implies a ghostly alter-ego hidden behind the reflecting surface (similarity 0.78)

Broader Connections

• Nearby reflecting surfaces constructively pile up wave reflections to amplify sound #corroborates (0.72)
• Conceptual confusion about sound reflection delayed its speed measurement for centuries #expands (0.70) — Eric J. Heller, Why You Hear What You Hear- An…, 151
• An echo is partly an original sound from the reflecting material #expands (0.70) — Gordon Hempton, John Grossmann, One Square Inch of Silence- One Man’s…, 927