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Napoleon, who understood Voltas contributions, was frustrated by the greater honors given Voltaire. He was reported by Victor Hugo to personally have modified a memorial to Voltaire at the library of the National Institute at Paris which read Au Grand Voltaire to Au Grand Volta. 2000 AD - Two Hundredth Anniversary of Voltas Invention His was a lifelong dedication to better understanding of electrical science
Why then is this Italian, his life, his times and his contributions so hidden that we may almost be unaware that the unit of one of the most fundamental electrical parameters, electrical potential, has been named the Volt in honor of his battery invention? On the surface, one might think that discovering the principles to create a battery was an end in itself, but by bringing it to the attention of the scientific world, Volta also provided the first continuous current source, which would be the foundations for communications, lighting, medical therapies and electromechanical power.
In 1660 Otto von Guericke constructed the first electrical machine, which generated electricity by the friction of a sulphur globe and demonstrated electrical attraction and sparks. Experimenters soon found that the electrical charge could be transported by a thread, and in the mid- 1700s, E.G. von Kleist invented the Leyden jar, the first capacitor that would store the charge generated by friction either by hand or by machine. Ben Franklin was to further electrical thinking by proposing a single electrical fluid rather than two (plus and minus) fluids. He became a fellow of the Royal Society in 1756. He is attributed with being the first to use the term electric battery to describe a collection of Leyden jars connected in series. Thus, Volta, in describing the results of his experiments, used the then known term electric battery which meant a string of capacitors. However, he extended the terminology to his newly discovered electrochemical batteries to have an inexhaustible charge. When Alessandro arrived into the world on February 18th, 1745, electrical knowledge was primitive, tools were equally sparse, and his early life was not easy. At age four he was not able to speak, and his father died when he was 7. Raised by his mother and uncle, he fended off family attempts to push him into a life in the church and as an attorney. After seminary school at 18, Volta obeyed his genius to study electricity independently. At this juncture he had three innate gifts which would carry him though to a monumental life of scientific contributions. First, he had an insatiable curiosity to understand the reasons behind phenomenon. The second gift was his ability to develop a scientific approach founded on the contributions of Gilbert, and third, he had a surprising talent for communicating with people everywhere in the scientific world of the time. When beginning his work, he first wrote letters to Nollet and Beccaria, the electrical authorities of the times, but Beccaria chastised his frivolity and recommended further readings and doing experiments. By age 20, Volta had experimental results and was able to dialogue with the experts and wrestle with the concepts on how they could be applied to his initial observations and data. By 1769 he published his first work on electrical attraction. During this period, he was to formulate a concept based on observation, which would be instrumental in his quest for the later understanding of Galvanis work and lead to his discovery of the battery. His published concept stated that only mixed bodies are electric. With growing recognition, he was appointed regent of the State Gymnasium in Como in 1774. Diverting his focus temporarily, Volta observed methane in swamps and described ways to use the gas for lanterns and an electric pistol. There was some connectivity to his electrostatic work because an electric spark could be used to ignite the pistol gas.
Volta continued to gain recognition with his communications skills. This recognition afforded him a trip to Switzerland and Alsac in 1777. Soon afterward, he was appointed to the professorship of physics at the University of Pavia. Although lesser scientists belittled Voltas mathematical skills, he properly interpreted his experimental results to mathematically define fundamentals which included describing the relationship of charge with Voltage and capacitance (Q = CT, where T is the tension of the charge as measured with an electrometer). He understood the need for universally accepted guidelines and recommended a standard for the fundamental unit of tension (Voltage) using a standard, charged metal disk on a balance at a standard distance above a conducting surface which is then counterbalanced by a standard weight. The unit is equal to about 13,350 Volts. Using this standard, he was able to correctly determine that the attractive force of charged bodies is proportional to (T/d) squared. Since electricity included lightning, and lightning was in the air, the study of meteorology and gasses became part of Voltas realm. He used his connectivity to build improvements to Saussures improved electrometer to sense even smaller charge and named it the condensator. Visiting with Lavosier and Laplace in France in 1782, the team worked on electrification in the change of state of water vapor, but they came up with erroneous results. Volta independently experimented with the sparking of gas and air over water. He wrote of his work to Lavosier, resulting in the Frenchmen obtaining water over mercury from the sparking. Lavosier and Laplace thought they had synthesized water, but Volta correctly believed they had analyzed gasses using his still accepted phlogiston chemistry. In 1784 he carried out experiments on partial pressures and sent the results in a letter to Lichtenberg. However, the general law of partial pressures is ascribed to Dalton, not Volta. Unfortunately, Volta lost his colleague Lavoisier to the French Revolutionists who did not like the tax collecting private company, Ferme Generale. Lavoisier, the founder of modern chemistry and a stockholder in the company, was executed by the Revolutionists in 1794. By 1790 Volta had all the tools in his possession for the unexpected grand challenge. This event was not to be an evolutionary happening, but rather a quantum type of jump based on the observations of his neighbor, Dr. Luigi Galvani, Professor at the University of Bologna. Galvani discovered that frog legs convulsed when a knife touched the crural or sciatic nerve by a person who was drawing a spark from an electrical machine. Galvani pursued the effects with Leyden jar discharges and atmospheric lightning. Twitching was even observed when two dissimilar metals connected the frogs main nerve and the leg nerve. Volta, the disciplined experimentalist, began to reproduce Galvanis work. As a reference, he repeated an experiment of Johann Sulzer, who in 1752 had reported that placing two touching pieces of metal (zinc and copper) on the tongue produced an unpleasant sensation. Opening the metal connection stopped the sensation. Volta decided to extend the experimentation and connected the metals to his eye where he sensed light flashes. He also connected coins to tinfoil, and then connected them to his tongue, producing a sour taste sensation. One day when placing one piece of metal to his forehead and a connecting it electrically to a different metal on his palate, a bright flash was sensed in his mind! He became convinced that the dissimilar metal conductors, not the animal tissues, were the source of the electricity. Volta wrote to Galvanis nephew, Giovanni Aldine in 1793, stating that the electricity came not from the animal power, but from the contact between the metal and unobserved impurities in the metal. Building more proof, Volta tested carbon conductors with a metal conductor and got similar results. His metallic electricity was beginning to take form. To develop rigorous fundamentals, he classified different combinations of metals as to their electromotive force (coined by Volta) and identified that those metals, farther apart in the stimulation list would produce greater results. This concept formed the basis of the standard oxidation potentials in aqueous solution. To complete the work, he had to improve electroscope sensitivity, so he improved a condensing electoscope which he had invented in 1782. With rigorous methodology, Voltas next goal was to multiply the potential. With the defined electromotive force of dissimilar metal pairs and series voltage addition, he first piled metal disks, one on top of each other, with no success. The resulting potential would only reflect the potential of the extreme disks in the pile. By 1796 he realized that the series pairs had to produce additive EMFs and discovered the crucial remedy, which was to add a moist conductor in the separated space between the metals to produce generating pairs. The results of the work were published in 1797.
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