Instruct: Given a question, retrieve passages that can help answer the question.
Query: When was the electrostatic machine invented?
Franklin was not the first to build an electrostatic generator. European scientists developed machines to generate static electricity decades earlier. In 1663, Otto von Guericke generated static electricity with a device that used a sphere of sulfur.[1] Francis Hauksbee developed a more advanced electrostatic generator around 1704 using a glass bulb that had a vacuum. He later replaced the globe with a glass tube of about 2.5 feet (0.76m) emptied of air.[1] The glass tube was a less effective static generator than the globe, but it became more popular because it was easier to use.[2]
The electrophorus is thus actually a manually operated electrostatic generator, using the same principle of electrostatic induction as electrostatic machines such as the Wimshurst machine and the Van de Graaff generator.
In 1663 Otto von Guericke invented a device that is now recognized as an early (possibly the first) electrostatic generator, but he did not recognize it primarily as an electrical device or conduct electrical experiments with it. By the end of the 17th Century, researchers had developed practical means of generating electricity by friction with an electrostatic generator, but the development of electrostatic machines did not begin in earnest until the 18th century, when they became fundamental instruments in the studies about the new science of electricity.
This was followed in 1660 by Otto von Guericke, who invented an early electrostatic generator. By the end of the 17th century, researchers had developed practical means of generating electricity by friction with an electrostatic generator, but the development of electrostatic machines did not begin in earnest until the 18th century, when they became fundamental instruments in the studies about the new science of electricity. The first usage of the word "electricity" is ascribed to Sir Thomas Browne in his 1646 work, "Pseudodoxia Epidemica". In 1729 Stephen Gray (1666–1736) demonstrated that electricity could be "transmitted" through metal filaments.
Wistarburgh Glass Works Corbett's electrostatic machine Van de Graaff generator
Through his research, Franklin was among first to prove the electrical principal of conservation of charge in 1747[16][24]: a similar discovery was made independently in 1746 by William Watson. Franklin wrote detailed letters and documents about his experiments with the electrostatic machine and Leyden jars.[16][34][35] In 1749, Franklin made a list of several ways in which lightning was similar to electricity.[36] He concluded that lightning was essentially nothing more than giant electric sparks, similar to the sparks from the static charges produced by his electrostatic machine.[36] He referred to static electricity as "electric fire", "electric matter, or "electric fluid."[32] The term "electric fluid" was based on the idea that a jar could be filled and refilled when it became empty.[3] That led to the revolutionary idea of "electrical fire" as a type of motion or current flow rather than a type of explosion.[37]
Frictional machines were, in time, gradually superseded by the second class of instrument mentioned above, namely, influence machines. These operate by electrostatic induction and convert mechanical work into electrostatic energy by the aid of a small initial charge which is continually being replenished and reinforced. The first suggestion of an influence machine appears to have grown out of the invention of Volta's electrophorus. The electrophorus is a single-plate capacitor used to produce imbalances of electric charge via the process of electrostatic induction.
In 1746, William Watson's machine had a large wheel turning several glass globes, with a sword and a gun barrel suspended from silk cords for its prime conductors. Johann Heinrich Winckler, professor of physics at Leipzig, substituted a leather cushion for the hand. During 1746, Jan Ingenhousz invented electric machines made of plate glass.[5] Experiments with the electric machine were largely aided by the discovery of the Leyden Jar. This early form of the capacitor, with conductive coatings on either side of the glass, can accumulate a charge of electricity when connected with a source of electromotive force.
Jan Rudolph Deiman and Adriaan Paets van Troostwijk used, in 1789, an electrostatic machine to make electricity which was discharged on gold electrodes in a Leyden jar with water. In 1800 Alessandro Volta invented the voltaic pile, and a few weeks later William Nicholson and Anthony Carlisle used it for the electrolysis of water. When Zénobe Gramme invented the Gramme machine in 1869 electrolysis of water became a cheap method for the production of hydrogen. A method of industrial synthesis of hydrogen and oxygen through electrolysis was developed by Dmitry Lachinov in 1888.
In 1898, the Pidgeon machine was developed with a unique setup by W. R. Pidgeon. On October 28 that year, Pidgeon presented this machine to the Physical Society after several years of investigation into influence machines (beginning at the start of the decade). The device was later reported in the Philosophical Magazine (December 1898, pg. 564) and the Electrical Review (Vol. XLV, pg. 748). A Pidgeon machine possesses fixed inductors arranged in a manner that increases the electrostatic induction effect (and its electrical output is at least double that of typical machines of this type [except when it is overtaxed]). The essential features of the Pidgeon machine are, one, the combination of the rotating support and the fixed support for inducing charge, and, two, the improved insulation of all parts of the machine (but more especially of the generator's carriers). Pidgeon machines are a combination of a Wimshurst Machine and Voss Machine, with special features adapted to reduce the amount of charge leakage. Pidgeon machines excite themselves more readily than the best of these types of machines. In addition, Pidgeon investigated higher current "triplex" section machines (or "double machines with a single central disk") with enclosed sectors (and went on to receive British Patent 22517 (1899) for this type of machine).
An electrostatic nuclear accelerator is one of the two main types of particle accelerators, where charged particles can be accelerated by subjection to a static high voltage potential. The static high voltage method is contrasted with the dynamic fields used in oscillating field particle accelerators. Owing to their simpler design, historically these accelerators were developed earlier. These machines are operated at lower energy than some larger oscillating field accelerators, and to the extent that the energy regime scales with the cost of these machines, in broad terms these machines are less expensive than higher energy machines, and as such they are much more common. Many universities worldwide have electrostatic accelerators for research purposes.
The linear accelerator could produce higher particle energies than the previous electrostatic particle accelerators in use when it was invented; the Cockcroft-Walton accelerator and Van de Graaff generator. In these machines, the particles were only accelerated once by the applied voltage, so the particle energy in electron volts was equal to the accelerating voltage on the machine, which was limited to a few million volts by insulation breakdown. In the linac, the particles are accelerated multiple times by the applied voltage, so the particle energy is not limited by the accelerating voltage.
These machines belong to a class of electrostatic generators called influence machines, which separate electric charges through electrostatic induction, or "influence", not depending on friction for their operation. Earlier machines in this class were developed by Wilhelm Holtz (1865 and 1867), August Toepler (1865), J. Robert Voss (1880), and others. The older machines are less efficient and exhibit an unpredictable tendency to switch their polarity. The Wimshurst does not have this defect.
In his electrotherapy, Bird used both electrochemical and electrostatic machines (and later also electromagnetic induction machines) to treat a very wide range of conditions, such as some forms of chorea. Treatments included peripheral nerve stimulation, electrical muscle stimulation and electric shock therapy. Bird also used his invention, the electric moxa, to heal skin ulcers.
Carré also conducted research in the field of electricity. In 1877, he invented an electric light regulator. He also invented the Carré machine, an electrostatic generator used to produce high voltages.
Wimshurst dedicated large amounts of his free time to experimental works. Besides his electrical activities, he invented a distinctive vacuum pump, a device to indicate ship stability and methods for electrically connecting lighthouses to the mainland. In 1878, he began to experiment with electrical influence machines for generating electrical sparks for scientific and entertainment purposes. Beginning in 1880, he became interested in electrostatic machines of the influence type. His house in Clapham, England, had a versatile workshop which had a wide variety of tools and devices for electric illumination. Wimshurst constructed several of the known types of electrostatic generators, such as those created by W. Nicholson, F. P. Carré and W. T. B. Holtz. To these predecessors, Wimshurst made many modifications with the result known as the Holtz-Wimshurst machine.
An electrophorus or electrophore is a simple manual capacitive electrostatic generator used to produce electrostatic charge via the process of electrostatic induction. A first version of it was invented in 1762 by Swedish professor Johan Carl Wilcke, but Italian scientist Alessandro Volta improved and popularized the device in 1775, and is sometimes erroneously credited with its invention. The word "electrophorus" was coined by Volta from the Greek ήλεκτρον ('elektron'), and ϕέρω ('phero'), meaning 'electricity bearer'.
Corbett's experiments with electricity and its principles shows his interest in science and medicine. The electrostatic machine and his electrical experiments in the early 1800s took place between Benjamin Franklin's electrical experiments of the mid-1700s and that of Thomas Edison's electrical inventions. The electrical principles of Corbett's electrostatic machine were later used by Edison.Citations
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Franklin distributed copies of the electrostatic machine to many of his close associates to encourage them to study electricity.[13] Between 1747 and 1750, Franklin sent many letters to his friend Collinson in London about his experiments with the electrostatic machine and the Leyden jar, including his observations and theories on the principles of electricity.[12] These letters were collected and published in 1751 in a book entitled Experiments and Observations on Electricity.[10][52][53][54]
Corbett's electrostatic machine is a high voltage static electricity generating device that was used by Shaker doctors for medical treatment in the early nineteenth century. Corbett's machine is in the collection of the Mount Lebanon Shaker Village in the state of New York USA.
In 1865 Holtz invented the "Holtz electrostatic influence machine", an electrostatic induction generator that converted mechanical work into electrostatic energy, needing only an initial charge to begin operation. In the following years, Holtz made modifications, and in the process, manufactured several more of the devices.
Multiple disk machines and "triplex" electrostatic machines (generators with three disks) were also developed extensively around the turn of the 20th century. In 1900, F. Tudsbury discovered that enclosing a generator in a metallic chamber containing compressed air, or better, carbon dioxide, the insulating properties of compressed gases enabled a greatly improved effect to be obtained owing to the increase in the breakdown voltage of the compressed gas, and reduction of the leakage across the plates and insulating supports. In 1903, Alfred Wehrsen patented an ebonite rotating disk possessing embedded sectors with button contacts at the disk surface. In 1907, Heinrich Wommelsdorf reported a variation of the Holtz machine using this disk and inductors embedded in celluloid plates (DE154175; "Wehrsen machine"). Wommelsdorf also developed several high-performance electrostatic generators, of which the best known were his "Condenser machines" (1920). These were single disk machines, using disks with embedded sectors that were accessed at the edges.
The concept of an electrostatic generator in which charge is mechanically transported in small amounts into the interior of a high-voltage electrode originated with the Kelvin water dropper, invented during 1867 by William Thomson (Lord Kelvin), in which charged drops of water fall into a bucket with the same polarity charge, adding to the charge. 
In a machine of this type, the gravitational force moves the drops against the opposing electrostatic field of the bucket. Kelvin himself first suggested using a belt to carry the charge instead of water. The first electrostatic machine that used an endless belt to transport charge was constructed during 1872 by Augusto Righi. It used an india rubber belt with wire rings along its length as charge carriers, which passed into a spherical metal electrode. The charge was applied to the belt from the grounded lower roller by electrostatic induction using a charged plate. John Gray also invented a belt machine about 1890. Another more complicated belt machine was invented during 1903 by Juan Burboa A more immediate inspiration for Van de Graaff was a generator W. F. G. Swann was developing during the 1920s in which charge was transported to an electrode by falling metal balls, thus returning to the principle of the Kelvin water dropper.
In 1878, the British inventor James Wimshurst started his studies about electrostatic generators, improving the Holtz machine, in a powerful version with multiple disks. The classical Wimshurst machine, that became the most popular form of influence machine, was reported to the scientific community by 1883, although previous machines with very similar structures were previously described by Holtz and Musaeus. In 1885, one of the largest-ever Wimshurst machines was built in England (it is now at the Chicago Museum of Science and Industry). The Wimshurst machine is a considerably simple machine; it works, as all influence machines, with electrostatic induction of charges, which means that it uses even the slightest existing charge to create and accumulate more charges, and repeats this process for as long as the machine is in action. Wimshurst machines are composed of: two insulated disks attached to pulleys of opposite rotation, the disks have small conductive (usually metal) plates on their outward-facing sides; two double-ended brushes that serve as charge stabilizers and are also the place where induction happens, creating the new charges to be collected; two pairs of collecting combs, which are, as the name implies, the collectors of electrical charge produced by the machine; two Leyden Jars, the capacitors of the machine; a pair of electrodes, for the transfer of charges once they have been sufficiently accumulated. The simple structure and components of the Wimshurst Machine make it a common choice for a homemade electrostatic experiment or demonstration, these characteristics were factors that contributed to its popularity, as previously mentioned.[9]
Before the connection between magnetism and electricity was discovered, electrostatic generators were invented. They operated on electrostatic principles, by using moving electrically charged belts, plates, and disks that carried charge to a high potential electrode. The charge was generated using either of two mechanisms: electrostatic induction or the triboelectric effect. Such generators generated very high voltage and low current. Because of their inefficiency and the difficulty of insulating machines that produced very high voltages, electrostatic generators had low power ratings, and were never used for generation of commercially significant quantities of electric power. Their only practical applications were to power early X-ray tubes, and later in some atomic particle accelerators.