One small but interesting subset in the study of rock art concerns the acoustics of rock art sites. According to some researchers it is possible to find interesting acoustics at many rock art sites. In locales where the rock art is on cliffs they believe that the form of the cliffs often provides for a stronger echo than other nearby sections of cliff. Measurements of the strength of echoes from various surfaces in painted European caves suggest that this can indeed be the case. In 2000 Lucy Rault wrote in Musical Instruments: Craftsmanship and Tradition from Prehistory to the Present, that “comparable investigations at Niaux have similarly demonstrated that in this cave places with particularly strong echoes also have images associated with them, some if these, significantly, mark places where sounds linger for several seconds. We can therefore conclude that the choice of locations for wall figures seems to have been made largely on the basis of their acoustical value. Sometimes whole walls remain empty where the corresponding space, however vast it may be, produces no echo. On the other hand, places favorable for echoes are marked and painted, even if their location made such decoration difficult to accomplish.” (Rault 2000:22).
Bison, Grotte du Portel, Ariege,France. From: Rault, p.23.
Given the strong echoes and reverberation found in these sites in the painted caves of Europe, we have to ask ourselves what were they echoing? The most obvious guess would be the sound of the animal depicted on the wall. The call of this creature might be imitated by spiritual leaders or vocally talented members of the clan. Another possibility could be the eerie moaning sound of a bullroarer. Regarding this, John Pfeiffer wrote in 1982 (p. 180) that “oval bone and ivory objects with abstract designs carved on them and a hole at one end make a high whining hum when whirled from a string, suggesting that the sound of a bullroarer moved people in the upper Paleolithic as well as in modern times” (Pfeiffer’s “high whining hum” would have come from a smaller bullroarer on a short string, a larger model on a longer string could give a much lower roaring sound). Especially in the case of a painted bison or other animal whose vocalizations are grunting, roaring, or rumbling sounds, hearing the sound of a bullroarer echoing and reverberating through the chamber would have been startling to say the least.
Another effect that can often be found in caves and rock shelters is the phenomenon of the whisper channel. When the walls are of the correct shape they will often pass the frequencies of a soft voice smoothly to the other end of the chamber in such a way that they are inaudible to people standing in between. I observed this effect in a rock shelter at Val Verde county in west Texas, where I could hear a soft conversation of people standing about 20 feet away at the other end of the shelter but individuals standing between us could not discern their comments.
A number of years ago, during a visit to the Grand Gallery of Horseshoe Canyon, in Canyonlands, Utah, one visitor had lugged a tape recorder and microphone all the way from the canyon rim to the panel and had set up his sound equipment while he walked back and forth along the rock art panels tapping the surface of the rock with a little hammer made of deer or elk antler. I thought at the time that this was a pretty silly practice, but I now see that it actually may have had some validity. Although I could not really see back then what the value would be in having that sort of information available, it is now obvious that it might add to the overall metadata of cultural knowledge of the people involved, and would allow evaluations based upon a broader knowledge of their cultural concerns, and this would benefit everyone interested in the prehistory of humanity.
REFERENCES:
Pfeiffer, John E.
1982, The Creative Exlosion: An Inquiry into the Origins of Art and Religion, Cornell University Press, Ithaca, New York.
Rault, Lucy
2000, Musical Instruments: Traditions and Craftsmanship from Prehistory to the Present, Harry N. Abrams, Inc., New York.