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The Education of Michael Faraday Over in England Michael Faraday begins his research in to electricity by publishing a series of scientific papers in 1821: Historical Sketches of the Electro Magnet, Contact in Voltaic Electricity, New Electro Magnetic Apparatus, and New Electro Magnetical Motions. In this paper Faraday is presenting applications of the Electro-magnetic field effect published in 1820 by Oersted. Technically Faraday creates the first two motors powered by electricity, although the rotating needle is not a motor, which could be used to power any thing. Sir Charles Wheatstone, the First Avant-Garde Musician His first experiments on the transmission of sound came from his observation of the distance between strings and sounding boards of different instruments. In one of Wheatstone's first acoustic experiments investigating the variation of distances and how those distances would effect sound, he attached a stretched a string to a steel bow and connected the bow to a soundboard of the piano through a glass rod nearly two meters long. Wheatstone found that the string sounded the same as if it were attached right to the sounding board. He then tried the same experiment with a tuning fork. The experiment would eventually become part of a performance piece at the theatre of the Royal Institution. After Wheatstone's studies of vibrations through solid bodies he creates his most famous instrument the "enchanted lyre" or the acoucryphone (Greek for "hearing a hidden sound"). The vibrations from a remote piano, which transmitted through a long wire, activated it. At just 19 years old Sir Charles Wheatstone gave the worlds first network music performance in his fathers music shop in Pall Mall, England1821. When Wheatstone played this instrument it was not a simple walk-on performance but more a musical installation. The enchanted lyre was suspended from the ceiling and circled by a velvet hoop supported on the floor by three rods. The horns of the lyre were like bugles bent down towards the floor and discs on both sides of the body of the instrument were of metallic appearance. The lyre was suspended by a brass wire, which passed through the ceiling and connected with the soundboards of instruments in a room above, where Wheatstone played pieces on the harp, piano, and the dulcimer. He used the string instruments for his "telemusic" pieces because it was easy for him to transmit sound over those devices as apposed to the flutes in which the only vibration was in a column of air. Tuned metal rods were sounded by vibrations coming from a distance through an obtrusive solid conductor. This appeared in an article entitled "The Repository of Music" which went on to predict the telecasting of operas and even "words of speech -- [these may be] susceptible of the same means of propagation". The concerts were conducted quite frequently and were very well received by the music critics who urged the public to go and hear the wonderful music of the "unseen performer". The high point of Wheatstone's music career came in 1822 when he conducted the sound of a whole orchestra in one of the shops along the Royal Arcade. The cost for the one-hour performance was 5 shillings. Wheatstone demonstrated both music and voice conduction with his "diaphonicon", a horizontal sound conductor running between rooms. Wheatstone continued his performances until the autumn of 1823. He continued to call himself a musical instrument maker even after his academic appointment as a professor at Kings College in London. There were many other instruments developed by Wheatstone throughout his lifetime. Among these instruments were two modified accordions known as the Concertina I and the Symphonium, which was different only in the fact that it was operated with a mouthpiece. The Concertina was very unique in that Wheatstone had devised a keyboard that was very user friendly. There were two lines of finger studs of such size and spacing that one finger could press a single stud or two adjacent studs in the same line. The notes were arranged so that the pressing of the two adjacent studs produced a chord, and the instruments were smaller and more portable. Wheatstone Visually Explains "Chladni Figures" Wheatstone met H.C. Orsted in 1823 in London. Orsted was in England conducting research on optics. Although Wheatstone was still working as an instrument maker his first research formal paper "New Experiments on Sound", had just been published. Orsted had read this paper written by the young Wheatstone and was very interested in the experiments, which related to the work of Ernst Florens Friedrich Chladni (1756-1827) a German physicist. Wheatstone had reproduced one of Chladni's experiments which dealt with visualizing sound waves and vibration. H.C. Orsted stated that he himself had reproduced Chladni's experiments but used alcohol and lycopodion powder instead of sand and attained similar results to Whetstones. Orsted was in his mid forties when he met Wheatstone who was only 21 at the time. Orsted encouraged Wheatstone continue his research and to publish the results in the scientific community. Ten years later we see noted in the proceedings of the Royal Society. His principle contribution to acoustics is a memoir on the so called Chladni’s Figures… probably the most remarkable of his early scientific labours". Published in "Philosophical Transactions of the Royal Society" in 1833 we see a long analysis of the complex Chladni’s figures that can be produced on a rectangular sounding plate. Wheatstone proved that all of Chladni’s figures, no matter how complex could be explained VISUALLY by a few simple patterns. "Acoustic Figures" was the last paper on sound which Wheatstone wrote. In this same year Herman Helmholtz the man who would write the definitive paper of the 19th century on sound, tone and vibration is born in Potsdam Germany. In 1824, Louis Braille's raised dots enabled the blind to read. In 1825 Ampere had been able to deduce an empirical law of forces (Ampere's Law) between two current-carrying elements, which showed an inverse-square law (the forces decreases as the square of the distance between the two elements, and is proportional to the product of the two currents). Later that year In England, William Sturgeon wrapped a wire around a soft metal bar to create the World's first electronic magnet. Several months after this experiment, Michael Faraday put a spinning magnet inside a horseshoe-shaped coil of wire, causing it to become electrified. In 1827 Ampere published his most famous work: "Memoirs sur la Theorie Mathematique des Phenomenes Electrodynamiques Unique des Phenomenes Electrodynamiques Uniquemant Deducete de l'Experience (Notes on Mathematical Theory of Electrodynamic Phenomena, Solely Deduced from Experiment). That same year Ernst Florens Friedrich Chladni, The Germany Physicist whose work would connect Hooke and Faraday dies. In 1829 Faraday writes Ampere about Sir Charles Wheatstones illustrations of the telegraph. In 1830 Samuel Soemmering, German inventor who developed the multi wire telegraph dies Frankfurt, Germany Joseph Henry, Inventor of the American Telegraph Joseph Henry was a professor of natural philosophy at the College of New Jersey which we know today as Princeton University, where he enjoyed a popular reputation with the students. While there Henry also lectured on geology and architecture and informally discussed metaphysics and other subjects. His areas of research widened at the university, although Henry's research maintained an ongoing theme of testing the relationships between electricity, magnetism, light, and heat. For example Henry used a thermoelectric apparatus to take the first factual measurements of the temperature differences between the solar surface and sunspots. He proved that the sunspots where cooler than the surrounding surface. This experiment also revealed new clues about the phenomena of limb darkening, the apparent coolness of the sun at its limb. Other research projects at the University included but were not limited to geophysics, meteorology, terrestrial magnetism, and auroras. In 1831, Joseph Henry builds and tests the first electromagnetic telegraph. He sends an electric charge through 5000 ft of wire, where an electromagnet produces a force on a suspended permanent magnet that swivels and rings a bell. Henry announced his work on electro-magnetic phoneme later that year. This time he took many layers of insulated wire and produced an electro-magnet of unmatched power. Several demonstrations proved that hybrid magnets could be activated over long distances, and (1) these experiments animated the concept of the telegraph for the first time in the United States. Henry also went on to invent the first electric motor later that same year. It is important to note that (2) Joseph Henry, independently of Michael Faraday in England, discovers mutual electromagnetic induction, the generation of electric current by magnetism, and electro-magnetic self-induction. Joseph Henry would in years to come explain the basic scientific principles of the telegraph to Samuel Morse who would later claim to be the sole inventor of the device. Henry and Morse shared a close friendship up until the patent legal battles over the telegraph, which turned them both into bitter enemies. (1) Webster's American Biographies- M. Rothenberg-G&C Merriam Company Publishers-1974 Pg480 (2) American National Biography - Oxford University Press-1999-Pg 614 Faraday's Visions of Electro-Magnetic Fields In 1831 Faraday published "Researches in Electricity" which changed the scientific view of how the world worked right up to the present day. At the request of the editor of Philosophical Magazine Faraday conducted several experiments in an attempt to further explain the very basic concept of electricity to the readers. While conducting these experiments, Faraday developed the concept in which circular 'lines of magnetic force' are wrapped around a wire carrying an electric current. (3) Faraday took note of Ernst Florens Friedrich Chladni (1756-1827) a German physicist who conducted several experiments where he took thin metal plates and covered them with sand and caused them to vibrate. The sand collected in nodal lines producing symmetrical patterns known as "Chladni figures". Chladni had taken these experiments directly from Robert Hooke work at Oxford University. Hooke had observed that "the motion of the glass was vibrate perpendicular to the surface of the glass, and that the circular figure of the flour changed into an oval one way, and the reciprocation of it changed it into an oval the other way". Faraday conceived and then constructed a model in which a suspended wire carrying an electric current moved in a circle around a fixed magnet, and in which a suspended magnet moved in a circle around a fixed wire carrying a current, each pushed by the magnetic field. This is the basic principle behind the dynamo, or the electric generator. " If electricity could generate magnetism, then magnetism ought to be able to generate electricity". Like Robert Hooke, Michael Faraday did not have a background in sophisticated mathematics and as a result of this did not articulate his discovery through a complex equation. He instead described his discovery on May 12th as a visual image of "lines of force" which create "an electro-magnetic field" or "fields of gravity" in the form of lecture given at the Royal Society. The title of the lecture was "On a Peculiar Class of Acoustical Figures and on Certain Forms Assumed by Groups of Particles Upon Vibrating Elastic Surfaces". This was followed by another lecture on June 18th "On the Arrangements Assumed by Particles on the Surfaces of Vibrating Elastic Bodies." The actual verification of this theory would be proved years later by Maxwell's equations. (3) (Gribbin, Pg 57) In 1832, Stephen Mitchell Yeates, inventor of the first hybrid telephone receiver, is born in Dublin, Ireland. The following year Karl Friedrich, Gauss, and Wilhelm Weber of Germany construct an electric telegraph that operates over a distance of 2 km or 1.25 miles, it uses a galvanometer as a receiving device. In 1835 Joseph Henry develops the basic principles of the telegraph. Henry also invents the electric relay, which enables a current to travel long distances from its origin. That same year Michael Faraday discovers independently of Joseph Henry the principle of self-induction. A year later Andrea Marie Ampere Dies in France. While back in England, independently of Joseph Henry, Edward Davy discovers the electric relay and applies it to the telegraph. In 1837 Philip Reis the inventor of the first articulating telephone was born on January 7th, Germany. Joseph Henry sets sail from the United States and begins his travels through Europe. Henry meets and mingles with many of the people in the scientific community. At one point Henry is invited to join Sir Charles Wheatstone in a telegraph experiment, which is conducted in the basement of King's College. Continue |