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 Fig. 6. The talking statues. They would be able to reproduce whispers from the square.
through the mouth of the statue: if it is a dog’s bark, the statue will bark, if someone sings, the statue will answer with singing and so on. If the wind blows, this will be taken into the spiral-shaped tube and the statue will be forced to emit very strong breaths. Applying the breath to a pipe, it will play. Bringing a trumpet near to the mouth of the stat- ue, the musical instrument will play and it will make innu- merable fun effects of this kind, provided that the spiral- shaped tube is disposed with the greatest of attention.”
Analyzing Fig. 6, the section of the conduit becomes nar- rower from the outside towards the interior, and therefore the air velocity increases to a considerable degree from left to right, inducing the talking effect in the statue. The acoustic mechanism which made the statue talk is substantially a microphone, which Kircher designed as a huge spiral-shaped tube, having the inner surface perfectly polished to reflect the waveforms. It was therefore able to convey the sound from outside into the room.
In the vertical version, (left side of Fig. 6 and in the back of the square) it seems to recall Borromini’s lantern of St. Ivo to the Sapienza, even if the inspiration for Kircher was in the “Grotta di Dionigi” in Syracuse. Giorgio de Sepi,4 who wrote the first catalogue of Kircher’s museum, described this talk- ing statue: “Kircher, in the laboratory of his room, has con- structed such a tube that the concierges can call him at the entrance, avoiding to go to his far apartment, but they can stop and call him with a usual voice from the garden.”
Sonorous voyeurism. Kircher devoted an entire chapter of his Phonurgia nova to the description of many gorgeous architectonic devices developed for worthy nobles, many of whom would have read, or heard, of his work. All these devices are fully illustrated and provided with extensive technical information about their construction.
The delectationes were specifically developed to amplify the voice, to communicate at a distance, to send music to dif-
ferent rooms, and even to eavesdrop. Kircher’s first described the invention regarding the singular location of cer- tain palatial royal chambers, in which every spoken or whispered word could be heard distinctly, not only in the same space, but also in other rooms. Having explained that con- duits suitable for directing sound and inserted into the walls should have a tubular or lengthened shape, Kircher indicated how to construct the build- ing (Fig. 7).
Three receivers D, Z, S, have exactly the same common origin E, corresponding to the window on the floor above (see the drawing in sec- tion).
“Inside the room, where the tube (D) captured and channelled the conver- sation, (i.e., the “D room”), there was a low narrow door, which, in case of
necessity, could be hermetically sealed. In addition there was a window with glass of a crystalline thickness. The same characteristics had to be shared by the rooms Z and S. Sound emitted in one of the rooms, not able to exit by the sealed door nor by the window, was directed toward DE, ZE, SE and conducted through secret conduits, reaching the people on the floor above.”
Following Kircher’s detailed description, such a device could be feasibly installed and function in a large building.
The “science of the echo”
The first book of the Phonurgia nova is called Phonosophia anacamptica, i.e., “the science of sound from the perspective of the echo.” Performing many experiments, Kircher studied the phenomenon of echo, beginning with its definition given by the Frenchman Marin Mersenne (1588-1648) in his Harmonie Universelle. Echo has two different meanings—in the first case echo is imago vocis—reflected (or repeated) voice. In the sec- ond meaning as expressed in Latin is resonance, from the Greek verb Ηχέω, (resound). This second meaning of echo is intended as the air in the cavities of a body, as within the Vitruvian vases, or in sound-chests.
The second section of the Phonosophia anacamptica is entitled Architectura echonica, and describes many experi- ments Kircher conducted with the phenomenon of echo (see Fig. 8). One of the more interesting experiments is regarding the obiectum phonocampticum, which refers to all the objects where the sound or the voice could be reflected, not only from walls and buildings, but also including trees, rivers, and metallic surfaces. During the explanation of his Echosophia (the “science of echoes”), Kircher found that air movement causes sound propagation, and wind propagation can influ- ence echo effects as well as weather conditions. This could be considered as one of the most relevant results Kircher achieved in the field of acoustics.
12 Acoustics Today, January 2009




















































































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