Popular Science Monthly/Volume 23/August 1883/Association of Colors with Sounds
POPULAR expressions are often very significant. "I saw three dozen lights of all colors," or some similar expression, may frequently be heard from persons who have received violent blows on the head or face. Under the influence of shocks of this kind, the eye really seems to see infinite numbers of sparks. Shocks of a certain class impressed upon the nervous system seem to have the faculty of producing phenomena of light. This remark has been suggested by the facts we are about to relate, which lead us to suppose that sonorous vibrations are susceptible in certain cases of provoking luminous sensations. There are, in fact, persons who are endowed with such sensibility that they can not hear a sound without at the same time perceiving colors. Each sound to them has its peculiar color; this word corresponds with red and that one with green, one note is blue and another is yellow. This phenomenon, "color-hearing," as the English call it, has been hitherto little observed.
Dr. Nussbaumer, of Vienna, appears to have been the first person who took serious notice of it. While still a child, when playing one day with his brother, striking a fork against a glass to hear the ringing, he discovered that he saw colors at the same time that he perceived the sound; and so well did he discern the color that, when he. stopped his ears, he could divine by it how loud a sound the fork had produced. His brother also had similar experiences. Dr. Nussbaumer was afterward able to add to his own observations nearly identical ones made by a medical student in Zürich. To this young man, musical notes were translated by certain fixed colors. The high notes induced clear colors, and the low notes dull ones. More recently, M. Pedrono, an ophthalmologist of Nantes, has observed the same peculiarities in one of his friends. M. Pedrono's friend had become so accustomed to the double perception of sounds and colors that he took no notice of it, and never told it to any one, having forborne to speak of it at the outset for fear of being considered singular. At one time several persons were amusing themselves by repeating in all kinds of applications, as a kind of joke, a slang expression which they had found in some story: "That is as fine as a yellow dog." So everything was declared to be as fine as a yellow dog. "Have you noticed his voice?" said one of the company; "it is as fine as a yellow dog." "Not at all," said M. Pedrono's friend, quickly, "his voice is not yellow, it is pure red." The observation was made in so earnest a manner that the whole company laughed out. "What!" they said, "a red voice! what do you mean?" M. X—— had to explain the curious faculty he had of seeing the color of voices. Each of the company, then, of course, wanted to know what was the color of his own voice, and M. X—— had to satisfy them all. It so happened that one of them had a yellow voice.
According to M. Pedrono, this friend of his had no trouble in his eyes or ears. His hearing was good, his sight perfect, and his general health excellent. Yet the chromatic sensitiveness was so sharp that the luminous impression seemed to be made a little while before the sonorous one; and, before it was possible to judge the quality and intensity of the sound, he had already seen and already knew whether it was red, blue, yellow, or of other color. He did not, like the Zürich student, perceive an appreciable change of color with every modification of tone. A sharp note was only brighter, a flat one duller, than the natural. But, when the same piece was played upon different instruments, varied sensations were produced. A Breton melody gave the sensation of yellow when it was played on a saxophone, red on a clarinet, and blue on the piano, showing that in this case the phenomenon was chiefly influenced by the timbre. The intensity of the color corresponds with the energy of the sound. Loud noises bring out brilliant colors. Very sharp tones determine a grayish sensation, that passes to a bright silver-white when they become intense. The human voice gives multifarious impressions. The vowels i and e (French) produce the most lively colors, a and o less defined ones, u a dark tint. Generally, with this subject, e gives yellow, a dark blue, o red or orange, u black. The diphthongs give combined colors: eu (French) is gray, oi clear gray, ue violet.
M. X—— can see all kinds of sounds and noises and distinguish all voices, but, curiously, can not perceive his own. When he is asked for the definite form under which he sees the sounds, he replies that the colored appearance is displayed on the vibrating object, the sonorous body. If the string of a guitar is twanged, that is what is colored; if the piano is touched, the color appears over the keys. The seat of color, he says, "appears to me to be principally where the sound is made above the person who is singing. The impression is the same if I do not see any one. There is no sensation in the eye, for I think of the same color with my eyes shut. It is the same when the sound comes from the street through walls and partitions. When I hear a choir of several voices, a host of colors seem to shine like little points over the choristers; I do not see them, but I am impelled to look toward them, and sometimes while looking toward them I am surprised not to see them."
These phenomena are strange; possibly the description of them may lead to the discovery of other equally singular examples, and it will become feasible to group them and look for an interpretation of them. It is now a question whether they are hallucinations, like the well-known ones of hearing voices and seeing phantoms, or whether they result from accidental confusion of the auditory and visual nervous fibers. As we now know that there are motor nerve-centers, specially adapted to particular functions, there may be also chromatic centers near the acoustic centers, and these different centers may echo to each other; and the acoustic fibers may cause synchronous vibrations at definite periods of the chromatic fibers. Without multiplying hypotheses, we have pointed out the facts, and must be satisfied to wait for the explanation of them till it is possible to make it.—Le Monde de la Science et de l'Industrie.