Strike the Fork Again and Place the Fork Handle in You Mouth Between Your Teeth
Hearing through Your Teeth
The Electrical Experimenter, vol. 3, no. 9, January 1916
Figure 1.
The following interesting experiment can be performed past anyone who has an ordinary disc phonograph. It is interesting, in so far as it shows the transmission of audio through the teeth, and through the bony substance of the human being skull, which in turn reacts upon the auditory nerve. [1] It is non well known but it is a fact nevertheless that sounds practise not necessarily take to enter through the aural opening in social club that we can hear sounds. Physicians in testing for hearing sometimes use a tuning fork which, after struck, is pressed with its lower part against the back of the skull, right behind the ear. The sound is then heard inside of the head the same equally if it had actually entered through the opening of the ear itself. This principle is made use of in the experiment described here, and while it is not electrical by whatever means, it probably will involvement every experimenter who owns a phonograph. [2]
Stop up both of your ears with cotton every bit tightly as possible so that no sound will exist heard from the outside. Now identify an ordinary darning needle between your teeth by bitter on it; hard, taking care at the aforementioned time that the lips or tongue do not touch the needle. The latter is important because if either lips or tongue impact the needle the sound will exist decreased considerably. For best results the needle itself should project not more than than i or 2 inches from the oral cavity. For that reason the darning needle should be broken off well-nigh one and half inches from its sharp betoken. It goes without saying that the precipitous indicate should project out of the oral fissure while the cleaved off terminate should be inside of the mouth.
At present start an ordinary disc phonograph and carefully press down upon the record with the needle's point held at the same bending every bit the reproducer's needle is held ordinarily. With a little practise ane will get proficient in moving the head at the aforementioned ratio of speed as the ordinary reproducer arm is moved from the outside of the record towards the inside. As soon as the needle touches the tape with sufficient pressure, the inside of the head will be filled immediately with music exceedingly loud and articulate. [3]
A curious issue of the experiment is that a person standing virtually by can hear the music, the head interim as a reproducer in this instance.
Of form, it will be understood that a totally deaf person will not be able to hear any sound if the auditory nervus is expressionless or inactive. It is, all the same, interesting to notation that partly deaf people can hear the music quite well. This is specially true of persons hard of hearing who cannot normally hear the sounds of a phonograph.
The writer should similar to hear from readers, particularly from those who are partly deaf, who take tried this experiment; the Electrical Experimenter will be glad to publish the results in subsequent issues. [4]
Notes
1 . This event'south installment of Baron Münchhausen's New Scientific Adventures includes a distant extrapolation of the bone-conduction technique in the grade of a technology that allows Martians to communicate as if telepathically. The story as well contains a digression in the form of an pedagogy transmission very similar to this one:
"Not far from the equator of the planet a central music found is operated by a single Martian, who, of class, is a musical genius. He operates one of the organ-like instruments of which I spoke before. The 'constitute' comprises besides the instrument, ii Tos rods each 20 feet high. These rods work exactly as the ones just described, except that they are operated at an enormous frequency. I have stood in front of them while they were operating, and so close, in fact, that I could have touched both rods with my hands. However, my ears detected not the slightest audio. But, incredible every bit it seems, millions of Martians were listening to the wonderful music at that infinitesimal, produced by these same rods, just non with their ears. They were listening with their brains! [. . .]
"Every Martian is required, for reasons which you will understand shortly, to wear a peculiar soft metallic cap. From the back of the latter a thin metallic cable runs down the Martian's back and is fastened there to his metallic coat. All Martian article of clothing, as well as footgear, is invariably of metal weave. At present equally all pavements and all floor, carpets, equally well every bit rugs, are metallic on Mars, for reasons which volition be apparent to you later, a metallic connexion with the earth or 'ground' is always effected.
"The metallic cablevision of which I merely spoke does non make contact with the cap itself, but it is insulated therefrom. Information technology connects, however, with a modest reddish metallic plate about the size of an American silverish dollar. This plate in plow, by ways of a apartment spring, presses confronting the temple of the wearer; the cap itself holds the plate in place. A similar plate presses against the other temple, but this plate, different the other, is continued metallicly [sic] to the cap itself. From this description you will assemble that the metallic cap performs the role of a wireless aerial, while the metallic clothing forms the ground. The two reddish plates pressing against the blank temples are made of 2 metals unknown on earth, and the metals are distributed over the surface of the plate in honeycomb fashion without touching each other. Now if the ii plates are pressed against the temples and when wireless waves are passing through them, the waves are translated into vibrations of a certain frequency. It has been found that if these vibrations reach the conscious sense of hearing which is located in the Temporal Lobe of the brain, sounds can exist impressed upon the brain without requiring the ear and its auditory nerve. In other words, the sound is "heard" directly inside the brain without the agency of the ear'due south mechanism.
"If this should be somewhat hazy to you a homely (though inaccurate) analogy will not be amiss here. At first chroma ane would retrieve that the ear is absolutely essential for hearing, but this is non the case. Try the post-obit unproblematic experiment: Finish up both your ears as tightly as possible with cotton so that you will not hear a audio from outside. If you are partly deaf—and I trust you are not—all the amend for the experiment. Place a darning needle betwixt your teeth by biting on it hard and take intendance that your lips do not touch the needle. The needle itself should project about i inch from your rima oris. Now operate an ordinary disc phonograph and with care press downward upon the record with the needle's betoken held at the same angle as the reproducer's needle is held ordinarily. Your whole brain will be filled immediately with music, exceedingly loud and articulate. Of course, in this case yous still hear with your ear'southward mechanism, the sound vibrations being carried to the eardrum through the bones of the head; but information technology is interesting to note that if a truly deaf person tries the experiment he will be enabled to "sense" the sounds, although not perfectly.
"Of grade, the function of the Martian apparatus is based on an entirely dissimilar principle, and the above experiment is only cited by mode of comparison."
two . Google Glass, the prototype head-mounted-display spectacles released in 2013, used the same principle of bone conduction technology to send audio to the user via a small oval-shaped component positioned behind the ear. Nathan Ingraham, "Google Glass Headset with Bone-Conduction Speakers Revealed in FCC Filing," The Verge , Jan 2013, http://www.theverge.com/2013/i/31/3938182/google-glass-revealed-in-fcc-filing .
3 . In 1923, Gernsback was awarded a patent for a device he chosen the Osophone and its "sound vibrations transmitted direct to the osseous tissue of the body." Hugo Gernsback, "Acoustic Apparatus," Dec 1924, http://www.google.com/patents/US1521287 .
iv . A profile of this experiment was published in the November 1923 event of Science and Invention as the cover story. See Are We Intelligent? in this book for an editorial that evokes what might be possible with such alternative forms of communication.
November 1923 encompass of Science and Invention.
Embrace story in the November 1923 Science and Invention .
Source: https://manifold.umn.edu/read/the-perversity-of-things-hugo-gernsback-on-media-tinkering-and-scientifiction/section/4f97c24f-e6e2-4b0a-8a23-430d73fbae68