Electric Sounds 185
whose attendant “ very high sound ” changed according the squares of the ratios he had
found: “ Imagine my astonishment in seeing this phenomenon that no one had ever seen
before. ”^6
These figures make visible the spatial patterns produced by sound waves, the correlation
between them brought home by the coincidence of sight and sound, especially as the pat-
terns suddenly change when the bow audibly excites a new standing wave in the plate.
Chladni ’ s discovery transcribed Lichtenberg ’ s electrical figures into sound on the implicit
presupposition that an analogous “ vibration ” lay behind the action of electric charge and
behind the sounding plate. Chladni went on to exhibit his figures throughout Europe. He
also invented two musical instruments (the euphonium and the clavicylinder), each an
offspring of his vibrating plates.^7
Chladni visited Paris in 1808 and demonstrated his figures to the Acad é mie des Sci-
ences, including Napoleon himself ( figure 12.3 ), showing the enormous interest evoked
by the wonderful spectacle of visible sound, audible sight. In the painting, Napoleon and
his entourage gaze thoughtfully on the demonstration, showing his celebrated interest in
exact science as he scrutinized a talisman of the new physics. Several French savants took
up Chaldni ’ s experimental program, particularly F é lix Savart, who began as a physician
but became “ truly Chladni ’ s professional successor. ”^8 Where Chladni had applied the
violin bow to various shapes of plates, Savart used the same techniques to study the violin
itself as a special kind of vibrating plate, exploring the relation between its structure and
its sound. In this way, Savart clarified the complex functions of the violin ’ s bridge
and sound post, part of artisanal violin-making that previously lacked theoretical explana-
tion. By locating the nodal lines, where sound waves would interfere and allow sand to
settle quietly, Savart showed that the best placement of the sound post — in French the
“ â me, ” the violin ’ s “ soul ” — avoided those nodes. After studying models based on Stradi-
vari and Guarneri violins, Savart thought he could improve the instrument ’ s basic design.
To maximize the violin ’ s symmetry, he built a trapezoidal violin with rectangular sound
holes, thereby simplifying the violin ’ s traditional curves and f -holes ( figure 12.4 ). Savart ’ s
novel violin was studied carefully by an eminent committee formed jointly by the Acad é-
mie des Sciences and the Acad é mie des Beaux-Arts, including the composer Luigi Cheru-
bini and also Savart ’ s older colleague, the physicist Jean-Baptiste Biot, who wrote the
report. Their unanimous opinion was that “ the new violin could pass for an excellent
violin, ” its tones even more suave than a standard instrument, though a bit more subdued
when heard close by.^9
The parallel strands in this intertwined story takes us to yet another country in which
a young savant made a new connection with Chladni ’ s work. In Denmark, Hans Christian
Ø rsted had drawn inspiration from Kant ’ s attempt to deduce natural philosophy from
basic forces of attraction and repulsion, which Ø rsted and others interpreted in the spirit
of contemporary Naturphilosophie. Charles-Augustin de Coulomb ’ s work in the 1780s
had offered persuasive evidence that electricity and magnetism involved two utterly