During an imperial tour of Egypt in 129 A.D., the emperor Hadrian visited the singing statute of Memnon at Thebes, a well-known spot in the Mediterranean world where the colossal seated figure of a pharaoh was known to sing at dawn. Greek and Roman tourists named the statue after Memnon, the Trojan hero who sang to his mother each morning at dawn. The statue lost its top half during an earthquake in 27 B.C., and thereafter began producing a strange sound “very like the twanging of a broken lyre string or harp string.” It is believed that the sound was caused by the sun’s rays heating cracks in the stone. Unfortunately, in the third century A.D., Septimus Severus had the statue restored, and it has been silent ever since.

Legend of the statue inspired a later thermacoustic designs: the memnonium, an instrument that self-generates music using solar energy.

But these are not the only singing stones. The singing statue of Memnon may have resulted accidentally, but there is a theory that the Maya purposely constructed pyramids with certain acoustic properties. Nico Declercq of Ghent University and his colleagues have shown how sound waves ricocheting around the tiered steps of the El Castillo pyramid, at the Chichén Itzá ruins near Cancún in Mexico, create sounds that mimic the chirp of the sacred quetzal bird or the patter of raindrops (see Acoustical Society of America article). There are reports of similar echo patterns at other Mayan sites.

It’s hard to know how deliberate this was, however — especially since the sound changes depending on whether the source is handclaps or something else like a drum.

For a more contemporary example, Ela Lamblin and Leah Mann gathered resonant slate from the Cascade mountains, stones from the Pacific Ocean, and rocks from the Applegate River to create a breathtakingly beautiful combination of sculptural stone, delicate movement, and symphonic sound. According to OddMusic, “The instrument is created with 100 river rocks suspended by music wire from a wing-shaped sound box and hanging in a steep arch. The strings (vibrating longitudinally) release their music as the performers dance and, with rosin-covered gloves, stroke, caress, and tug the strings.” You can listen to a musical sample at OddMusic.

[Photo: The Colossi of Memnon, detail of a chromolithograph by Ernst Weidenbach made after a Prussian archaeological expedition to Egypt in 1842-45. The singing statue Memnon is the one on the right. Public domain image.]