Category: Timeline Stories

Lee De Forest (1873–1961) was a remarkable American inventor with over 180 patents to his credit. He took credit for the Audion, the first vacuum triode, a vacuum tube that takes relatively weak electrical signals and amplifies them. De Forest is one of the fathers of the electronic age, as his Audion helped to usher in the widespread use of electronics. He is also credited with one of the principal inventions which brought sound to motion pictures.

Born in Council Bluffs, Iowa, (a son of a minister), Ph.D. in electrical engineering from Yale University (1899), Lee De Forest was a rather controversial person—he was involved in several patent lawsuits and spent a substantial part of his income from his inventions on the legal bills. De Forest had four marriages and several failed companies, he was defrauded by business partners (and defrauded business partners himself), and he was once indicted for mail fraud but was later discharged.

The Audion (also called the De Forest valve, and since 1919 known as the triode) was a result of De Forest’s interests in wireless telegraphy. It was invented in early 1906, and in August of the same year, De Forest filed a patent for Improvement in Wireless Telegraphy. The Audion actually was a bulb with the same contents as the Fleming diode, except for an added electrode, but De Forest always claimed, that he didn’t know about the Fleming diode.

De Forest was granted a patent for his early two-electrode version of the Audion on 15 Jan. 1907 (US Patent No. 841386), as the triode (three electrodes) version was patented in 1908 (US Patent 879532). It was the forerunner of the triode, in which the current from the filament to the plate was controlled by a third element, the grid. A small amount of power applied to the grid could control a larger current from the filament to the plate, allowing the Audion to both detect radio signals (that is, make them audible) and provide amplification. However, De Forest’s Audion is quite distinct from the true vacuum triode in that it is not capable of linear amplification, not to say for the semiconductor transistor, which is a base element of every electronic computer. In fact, Lee de Forest initially considered his triode simply as a more sensitive type of diode detector. Several years later, in 1911, the young undergraduate at Columbia University Edwin Armstrong was the first to recognize that the triode could operate as an amplifier.

In Forest’s original design, a small metal plate was sealed into the lamp housing, and this was connected to the positive terminal of a 22-volt battery via a pair of headphones, the negative terminal is connected to one side of the lamp filament. When wireless signals were applied to the wire wrapped around the outside of the glass, they caused disturbances in the current which produced sounds in the headphones.

This was a significant development as existing commercial wireless systems were heavily protected by patents and a new type of detector would allow De Forest to market his own system. He eventually discovered that connecting the antenna circuit to a third electrode placed directly in the current path greatly improved the sensitivity. In his earliest versions, this was simply a piece of wire bent into the shape of a grid-iron (hence “grid”).

Compared to all competing devices at the time, the Audion was unique in that it did not draw significant power from the antenna/tuned circuit, which allowed the tuning circuitry to operate with maximum selectivity. With virtually all other systems, all of the power to operate the headphones had to come from the antenna circuit itself, which tended to “damp” the tuned circuits, limiting their ability to separate stations.

In the world of computers, the scanner is a device that optically scans images, printed or written text, a three-dimensional object, etc. representing it in a digital format. The now ubiquitous device can be found in offices as a desktop (or flatbed) scanner, where the document is placed on a glass window for scanning; in engineering and creative labs as a 3D scanner, used for industrial design, reverse engineering, test and measurement, gaming and other applications; in printing shops as very-high-quality drum scanners, that are superior in resolution, color gradation, and value structure. So, who invented the scanner?

In early 1957, Russell Kirsch (1929-2020), a 27-year-old computer scientist and a new father, brought a 5×5 cm photograph of his few months old baby (see the nearby image) to his office at the National Bureau of Standards, where he was one of the few people authorized to work on the Standards Electronic Automatic Computer (SEAC), the first programmable computer in the United States.

Kirsch wanted to know “What would happen if computers could see the world the way we do?”. To test his question, he chose a recent photograph of himself smiling proudly at his firstborn child. The boy rests in the crook of his elbow, gazing wide-eyed into the camera that captured the moment in black-and-white. The full image contained more information than the computer could process, so Kirsch snipped out a small piece containing just the baby’s face. He ran the image through a scanner and program that he and his colleagues had fashioned.

It occurred to Russel Kirsch that a general-purpose computer could be used to simulate the many character recognition logics that were being proposed for construction in hardware. This would require an input device that could transform an image into a form suitable for storage in the memory of a computer. Voilà, the scanner was born.

The SEAC scanner used a rotating drum and a photomultiplier to sense reflections from a small image mounted on the drum. A mask interposed between the picture and the photomultiplier tessellated the image into discrete pixels. The first image ever scanned (see the nearby image) had a resolution of 176 pixels on a side.

A further important advantage of building such a device was that it would enable programs to be written to simulate the various ways in which humans view the visible world. A tradition had been built in which simple models of human structure and function had been studied, for example, in neuroanatomy and neurophysiology. The emphasis on binary representations of neural functions led us to believe that binary representations of images would be suitable for computer input. This serious mistake was implemented in the first image scanner built.

A serial-parallel converter (staticizer) was connected to the SEAC memory, enabling a stored image to be displayed on a cathode ray oscilloscope, thus making it possible for the researchers to see what the computer saw. And when they could see binary images, they realized the limitations of binary representation. So they experimented with superimposing multiple scans at different scanning thresholds and the use of time-varying thresholds for pulse density modulation to represent multiple gray levels in an image.

The modern scanner may be considered the successor of early fax and telephotography input devices from the 19th century. The first “fax” device was developed in the early 1840s by the Scottish inventor Alexander Bain (1811–1877), who is primarily known as the inventor of the first electric clock in 1841. On 27 May 1843, Bain received a British patent (№9745) for improvements in producing and regulating electric currents and improvements in timepieces and in electric printing and signal telegraphs, and later made some improvements in his next patent (№10838), granted on 25 September 1845.

Alexander Bain (see the nearby image) was born on 12 October 1811 in the little town of Thurso, in the extreme north of Scotland, in a poor crowded family (he had six sisters and six brothers) of a crofter. Bain had a tough childhood and did not excel in school, but at the age of twelve, he went to hear a penny lecture on science which, according to his own account, set him thinking and influenced his whole future. He was apprenticed to a clockmaker in Wick. Learning the art of clockmaking, Bain went to Edinburgh, and subsequently in 1837 to London, where he obtained work in Clerkenwell, then famed for its clocks and watches. In London Bain frequented the lectures at the Polytechnic Institution and the Adelaide Gallery and later constructed his own workshop on Hanover Street.

Bain began inventing in the 1830s, developing inkstands, ink holders, a ship’s log, and later many electrical devices, including various types of automatic telegraphs, an electric clock, an earth battery, insulation for electric cables, and an electric fire alarm for the army.

In his experimental facsimile apparatus from 1843 (see the nearby drawing), using his experience as a clockmaker, Bain used a clock to synchronize the movement of two pendulums for line-by-line scanning of a message. As a reading/writing device, he used a stylus that was an electrically conductive swinging pendulum. As the pendulum swung back and forth across a raised image on a copper plate, electrical pulses are generated. Besides that, each swing of the pendulum moved the copper plate to a small step so that the pendulum was able to scan the entire plate surface.

The electrical pulses were then sent across five wires to a receiving device, that also featured a pendulum. Its pendulum was synchronized with the sending device pendulum, which allowed the receiving side to generate an exact replica of the original image, using electrochemically sensitive paper impregnated with a chemical solution of ammonium nitrate and potassium ferrocyanide.

In his patent description, Bain claimed that a copy of any other surface composed of conducting and non-conducting materials can be taken by these means, but actually, his mechanism reproduced poor-quality images and was not a viable device mainly because the transmitter and receiver were never truly synchronized.

Bain’s concept of the fax was somewhat improved in 1848 (British patent 12352) by the English physicist Frederick Bakewell (1800–1869), but Bakewell’s device (see the lower patent drawing) also reproduced poor-quality images.

In 1846 Alexander Bain greatly improved the speed of telegraph transmission by using punched paper tape (nicknamed ticker tape because of the ticking sound the telegraph made) to send messages. This procedure will speed up the transmission of information very much.

The punched paper tape was introduced by Bain on 12 December 1846, when he patented the so-called chemical telegraph. He had seen that the Morse and other telegraphs then in use were comparatively slow, due to the mechanical inertia of their moving parts, and realized that the signal current could be used to make a readable mark on a moving paper tape soaked in a mixture of ammonium nitrate and potassium ferrocyanide, which gave a blue mark when a current was passed through it.

Bain’s chemical telegraph was tried in France between Paris and Lille, and attained a speed of 282 words in 52 seconds, a great advance on Morse’s telegraph which could only give about 40 words per minute. Later it was used in England and USA, but never really entered general usage.

The first practical operating electromechanical commercially exploited fax machine, the Pantelegraph, was invented in 1861 by the Italian physicist Giovanni Caselli (1815-1891).

Made of cast iron and standing more than two meters high, this primitive to our mind, but effective machine worked as follows: The sender wrote a message on a sheet of tin using non-conducting ink. The sheet was then fixed to a curved metal plate. The stylus of the transmitter scans an original document by moving across its parallel lines (three lines per millimeter). The signals were carried by telegraph to the marked out the message in Prussian blue ink, the color produced by a chemical reaction, as the paper was soaked in potassium ferrocyanide. To ensure that both needles scanned at exactly the same rate, two extremely accurate clocks were used to trigger a pendulum which, in turn, was linked to gears and pulleys that controlled the needles.

One of the first adding machines with full keyboard construction in Germany and Europe was created around 1890 by the engineer Heinrich Proskauer in Berlin. Later the construction of Proskauer was implemented in Sumlock Duolectric 912/C adding machine, which had a supporting electric drive.

Heinrich Proskauer received two German patents for his Additionsmaschine: №65597 from 25 December 1891 and №69251 from 10 May 1892.

The adding machine of Proskauer was similar to Comptometer, the first commercially successful key-driven mechanical calculator, patented in the United States by Dorr Felt. Its numeric keys worked without locking, and the repetition function was not possible.

Biography of Heinrich Proskauer

Unfortunately, little is known about the inventor of this interesting machine—Heinrich Proskauer. He was a German Jew, born on 14 March 1853 in Kreuzburg (Oberschlesien), Kingdom of Prussia (now Kluczbork, a small town in southern Poland). He was the last child (of eight) of Adolph Abraham Proskauer (1803-1875), and Johanna Goldberg-Proskauer (1814-1884). In April 1889 Heinrich Proskauer married in Berlin to his cousin Jenny Unger (1863-1915), and they had three sons (sadly, all of them died in infancy): Siegfried (1892-1892), Martin (1894-1895), and Hans (1897-1898). Heinrich Proskauer died in 1925 in Berlin.

In the first half of the 20^th century, vacuum tubes allowed the development of radio broadcasting, long-distance telephone service, television, and the first electronic digital computers, which were the largest vacuum-tube systems ever built. So, who and when invented the vacuum tube? Let’s meet the English scientist John Ambrose Fleming.

John Ambrose Fleming (1849–1945) was an English electrical engineer and physicist, known primarily for inventing in 1904 the first vacuum tube, also called a thermionic valve, vacuum diode, kenotron, thermionic tube, or Fleming valve. Fleming made numerous contributions not only to electronics, but also to photometry, electric measurements, and wireless telegraphy. He became a consultant to the Edison Electric Light Company and a popular teacher at University College. Fleming was knighted in 1929 for the many advances he had made to electrical and electronic engineering. He was the author of more than a hundred scientific papers and books, including the influential “The Alternate Current Transformer” (1889), “The Principles of Electric Wave Telegraphy” (1906), “The Propagation of Electric Currents in Telephone and Telegraph Conductors” (1911) and “Memoirs of a Scientific Life” (1934).

In 1904 Fleming was granted GB patent №24850 (see the patent) for Improvements in Instruments for Detecting and Measuring Alternating Electric Currents (the prototype of the vacuum tube), next year he received a US patent for the same device (US pat. 803684). This invention (see the nearby photo for one of the first vacuum diodes of Fleming) is often considered to have been the beginning of electronics, for this was the first vacuum tube. Fleming’s diode was used in radio receivers and radars for many decades afterward until it was superseded by solid-state electronic technology more than 50 years later. In the middle of the 20^th century, transistors replaced tubes in virtually all applications, but they are still occasionally used in display devices for television sets and computers (cathode-ray tubes), in microwave ovens, and as high-frequency transmitters on space satellites.

The Fleming’s vacuum tube was based on an effect that Thomas Edison had first discovered in the 1880s, and had not put to useful work at the time. One of Edison’s inventors—William Joseph Hammer (1858-1934), working in Thomas Edison’s laboratory, noted the rectifier effect when he added another electrode to a heated filament light bulb. Hammer was in charge of testing early light globes in 1880-81 and noted a blue glow around the positive pole in a vacuum bulb and a blackening of the wire and the bulb at the negative pole. This unknown phenomenon was first called “Hammer’s Phantom Shadow,” but when Edison patented the bulb in 1883 it became known as the “Edison Effect.”

Fleming’s vacuum tube essentially consisted of an incandescent light bulb with an extra electrode inside. When the bulb’s filament is heated white-hot, electrons are boiled off its surface and into the vacuum inside the bulb. If the extra electrode (also called a “plate” or “anode”) is made more positive than the hot filament, a direct current flows through the vacuum. And since the extra electrode is cold and the filament is hot, this current can only flow from the filament to the electrode, not the other way. So, AC signals can be converted into DC.

The first cathode-ray tube (CRT) was built in 1897 by the famous German physicist Karl Ferdinand Braun (1850-1918). The invention of Braun was based upon the work of many other scientists, as is the case with almost all inventions. Who was the first in this area?

The history of Cathode Ray Tube can be followed back to (at least) 1854 when the skilled German glassblower and mechanic Heinrich Geissler (Geißler) (1814-1879) was asked by the professor of mathematics and physics in Universität Bonn (University of Bonn) Julius Plücker (1801-1868) to design an apparatus for evacuating a glass tube.

Johann Heinrich Wilhelm Geißler, born in Igelshieb, Thuringen, descended from a long line of craftsmen in the Thüringer Wald and in Böhmen. He worked for years through Germany and the Netherlands as an instrument maker (together with his brothers, also glassblowers), eventually including the University of Bonn, where he finally settled down in 1852 in a workshop of his own, as an instrument-maker for the production of Physical and Chemical instruments. In 1855 Geissler was rewarded with the gold medal at the Exposition Universelle (World Exhibition) in Paris due to his excellent work on fine glass.

Julius Plücker was a famous German mathematician, who made fundamental contributions to analytic and projective geometry, but in the 1840s he turned away from mathematics and concentrated on physics. In 1847 he began research on the behavior of crystals in a magnetic field, establishing results central to a deeper knowledge of magnetic phenomena. The order of the apparatus for evacuating a glass tube to Geißler was made in relation to similar research—to concentrate the light for his spectral research.

Geißler was interested in these tubes from the experiments of his brother Friedrich in the Netherlands. Friedrich Geißler had made earlier these massonic tubes (filled with mercury vapor) in Amsterdam for the Dutch Chemists Volkert Simon Maarten van der Willigen. So in 1855, Heinrich Geissler developed a hand-crank mercury pump (with this pump he was able to reach very low-pressure levels) and glass tubes that could contain a superior vacuum (the Geißler Tube), a low-pressure gas-discharge tube made of glass. Plücker owed his forthcoming success in the electric discharge experiments (Plücker inserted metal plates into the Geissler tube and noticed a pale green light at the positive end of the tube, and in 1858 shows that cathode rays bend under the influence of a magnet suggesting that they are connected in some way) in large measure to Geissler.

The future value of Plücker and Geissler’s research toy, apart from neon lighting, would be fully realized only some 50 years later, in 1897, when Karl Ferdinand Braun introduced a CRT with a fluorescent screen, known as the cathode ray oscilloscope, and in 1905, when Lee De Forest invented the Audion vacuum tube, creating the entire basis of long-distance wireless radio communications and electronics. But it was a long way to go to Braun and De Forest.

Geissler’s tubes went soon to other countries like France and England, to researchers like Faraday, Crookes, and Hittorf which he sent 50 tubes for research in 1858, the many experiments which followed led to many new discoveries.

In 1865 the German chemist Hermann Sprengel improves the Geissler vacuum pump. In 1869 the German physicist Johann Wilhelm Hittorf finds that a solid body put in front of the cathode cuts off the glow from the walls of the tube and establishes that rays from the cathode travel in straight lines.

In 1871 the English engineer Cromwell Fleetwood Varley published a suggestion that cathode rays are composed of particles. William Crookes proposes that they are molecules that have picked up a negative charge from the cathode and are repelled by it.

In 1876 the German physicist Eugen Goldstein shows that the radiation in a vacuum tube produced when an electric current is forced through the tube starts at the cathode and introduced the term cathode ray to describe the light emitted. Later in 1876 Goldstein observes that a cathode-ray tube produces, in addition to the cathode ray, radiation that travels in the opposite direction. These rays are called canal rays because of holes (canals) bored in the cathode; later these will be found to be ions that have had electrons stripped in producing the cathode ray.

In 1883 Heinrich Hertz shows that cathode rays are not deflected by electrically charged metal plates, which would seem to indicate (incorrectly) that cathode rays cannot be charged particles. Later in 1892, he concluded (incorrectly) that cathode rays must be some form of a wave, showing that the rays can penetrate thin foils of metal, which he takes to support the wave hypothesis.

The above-mentioned and many other discoveries led to the 1897 invention of the famous German physicist Karl Ferdinand Braun (who played also an important role in the development of semiconductor devices) when he built the first cathode-ray tube (CRT) and cathode ray tube oscilloscope (see the upper image). Braun shared the Nobel Prize for Physics in 1909 with Guglielmo Marconi for the development of wireless telegraphy. However, he is still best known for his invention of the cathode ray tube and the first oscilloscope.

The development of the cathode ray tube greatly facilitated the development of a practical television system. In 1907, the Russian scientist Boris Rosing (working with his student Vladimir Zworykin) used a CRT in the receiver of a television system that at the camera end made use of mirror-drum scanning. Rosing transmitted crude geometrical patterns onto the television screen and was the first inventor to do so using a CRT. In 1929 Zworykin invented the cathode-ray tube called the kinescope, sorely needed for television.

It seems the first computer, which used a CRT monitor, was the US military SAGE from the 1950s. SAGE had more than 150 display consoles housing a 48-inch long Vector CRT. The first commercial computer equipped with a CRT monitor was Digital Equipment’s PDP-1 from 1959.

After his work for Bell Laboratories since 1928, mostly on vacuum tubes, including improvements of Radar during World War II, the distinguished electrical engineer Arthur Lee Samuel (1901-1990), became a professor of electrical engineering at the University of Illinois at Urbana–Champaign, where he initiated the ILLIAC project. ILLIAC (Illinois Automatic Computer) was a series of supercomputers, built at a variety of locations. In 1949, Samuel left the University before its first computer was complete, and joined IBM’s Poughkeepsie Laboratory in New York, where he would conceive and carry out his most successful work. Samuel is credited with one of the first software hash tables, and influencing early research in using transistors for computers at IBM. There he also continued his seminal research on machine learning.

Still in Illinois, working on ILLIAC, Samuel and his team stumbled upon a problem—by the end of 1948 the project was running out of money. Someone suggested that in order to attract attention they should build a cut-down machine and do something “dramatic” with it. Samuel had heard about Claude Shannon’s work on programming a computer to play chess and he decided that the thing to do was to program his machine to play checkers (draughts), because it is relatively simple, but has a depth of strategy. He reasoned that if Shannon had already done it for chess: it ought to be dead easy to program a computer to play checkers. Samuel’s idea was partly motivated by the fact that the world championships was to be held in a neighboring town. The idea was presumably that they would produce a computer that would win.

So Samuel started to write a program certain of the knowledge that it had all been done before, but actually it hadn’t. Claude Shannon had just talked about it all in the most general terms and hadn’t got anywhere near a computer. At the beginning of 1949, Samuel made a trip to Chicago to talk to Shannon where he discovered the terrible truth. Undaunted, he decided that checkers had been a good choice after all and set about the programming: I started writing a program for a machine that did not exist, using a set of computer instructions that I dreamed up as they were needed.

Samuel soon realized that the small demonstration machine was going to be as complex as the real thing and running out of money was inevitable. Moreover, not being able to pursue computers drove him to seek a new job at a better salary. Thus by the spring of 1949, he moved to IBM at Poughkeepsie.

In Poughkeepsie, while working on IBM’s first stored program computer, the 701, Samuel found himself talking with one of the chief designers of the computer, about the word size that should be used—32 or 36 bits. Then he started to ask himself which would be better for his checkers playing program and, to find out, he started to write it again but using the instruction set of the unfinished 701. Later Samuel realized that teaching computer to play games is very fruitful for developing tactics appropriate to general problems—I became so intrigued with this general problem of writing a program that would appear to exhibit intelligence that it was to occupy my thoughts during almost every free moment for the entire duration of my employment by IBM and indeed for some years beyond. The main driver of the machine was a search tree of the board positions reachable from the current state.

Samuel was the first person to do any serious programming on the 701 and as such had no system utilities to call on. In particular, he had no assembler and had to write everything using the opcodes and addresses. As he had only a very limited amount of available computer memory, he implemented what is now called alpha-beta pruning. Instead of searching each path until it came to the game’s conclusion, Samuel developed a scoring function based on the position of the board at any given time, which tried to measure the chance of winning for each side at the given position. The function took into account such things as the number of pieces on each side, the number of kings, and the proximity of pieces to being kinged.

The program chose its move based on a minimax strategy, meaning it made the move that optimized the value of this function, assuming that the opponent was trying to optimize the value of the same function from its point of view.

Possessing great creativity and essentially working alone, doing his own programming, Arthur Samuel also designed various mechanisms by which his program could improve its skills. In what he called rote learning (or generalization learning), the program remembered every position it had already seen, along with the terminal value of the reward function. This technique effectively extended the search depth at each of these positions. He also used underlying techniques such as mutable evaluation functions, hill climbing, and signature tables.

Eventually, the 701 was built and it incorporated some changes to the instruction set suggested by Samuel as the result of his work on checkers. Being the first really large non-numerical program it influenced the instruction set of all subsequent IBM machines. As Samuel was frightened that the machine might never be completed or that it might be radically changed, he wrote the checkers program as a set of small self-contained modules loaded by a central module—a sort of primitive operating system. He got it all to run on the first experimental model of the 701.

Later programs reevaluated the reward function based on input from professional gamers. Samuel also had it play thousands of games against itself as another way of learning. With all of this work, his program reached a respectable amateur status and was the first to play any board game at this high a level. After his retirement from IBM in 1966, Samuel continued to work on checkers until the mid-1970s, at which point his program achieved sufficient skill to challenge a respectable amateur.

Samuel completed his first checker program on the IBM 701, and when it was about to be demonstrated, Thomas J. Watson, Sr., the founder, and president of IBM remarked that the demonstration would raise the price of IBM stock by 15 points. It really did. Samuel was eventually put in charge of a pure research effort after persuading the Watsons that IBM needed to do pure research and not just product development.

Alonzo Church (14 June 1903—11 August 1995) was an eminent US mathematician and logician with works of major importance in mathematical logic, recursion theory, and in theoretical computer science. He is best known for the lambda calculus, Church–Turing thesis, proving the undecidability of the Entscheidungsproblem, Frege–Church ontology, and the Church–Rosser theorem.

In 1936, Church created a method for defining functions called lambda calculus (λ-calculus). Within λ-calculus, he defined an encoding of the natural numbers called the Church numerals. A function on the natural numbers is called λ-computable if the corresponding function on the Church numerals can be represented by a term of the λ-calculus (which is equivalent to using general recursive functions).

In the same 1936, before learning of Church’s work, Alan Turing (Turing arrived at Princeton in 1936 and Alonzo Church was Turing’s Ph.D. Advisor) created a theoretical model for machines, now called Turing machines, that could carry out calculations from inputs by manipulating symbols on a tape. Given a suitable encoding of the natural numbers as sequences of symbols, a function on the natural numbers is called Turing computable if some Turing machine computes the corresponding function on encoded natural numbers.

In computability theory, the Church–Turing thesis is a hypothesis (“thesis”) about the nature of computable functions. In simple terms, the Church–Turing thesis states that a function on the natural numbers is computable in an informal sense (i.e., computable by a human being using a pencil-and-paper method, ignoring resource limitations) if and only if it is computable by a Turing machine.

In 1941 Church wrote the monograph The Calculi of Lambda-conversion, which was later useful to others in the development of semantics for programming languages. Today the λ-calculus is a major research topic in theoretical computer science.

Among the many awards that Church received were his election to the American Academy of Arts and Sciences in 1967 and his election to the National Academy of Sciences, and to the British Academy, both in 1978. As one of his colleagues remembered, “Church read everything and forgot nothing”. When asked what made Church a world-class scholar, he had a remarkably simple answer: “He was just smarter than anybody else.”

Alan Mathison Turing (1912–1954) was an extremely gifted man, who was influential in the development of computer science and provided a formalization of the concept of the algorithm and computation with his famous Turing machine, playing a significant role in the creation of the modern computer. Turing discovered something that would have delighted Leibniz—he found that it was possible, in principle, to devise one single universal machine that, all by itself, could carry out any possible computation.

Turing first described the Turing machine in his 1936 article On Computable Numbers, with an Application to the Entscheidungsproblem.

The Turing machine is an idealized computing device, consisting of a read/write head (or scanner) with a paper tape passing through it. The tape is divided into squares, each square bearing a single symbol (0 or 1, for example). This tape is the machine’s general-purpose storage medium, serving both as the vehicle for input and output and as a working memory for storing the results of intermediate steps of the computation. In the original article of 1936, Turing actually imagines not a mechanical machine, but a person whom he calls the computer, who executes these deterministic mechanical rules in a desultory manner.

The input that is inscribed on the tape before the computation starts must consist of a finite number of symbols. However, the tape is of unbounded length, for Turing’s aim was to show that there are tasks that these machines are unable to perform, even given unlimited working memory and unlimited time. The read/write head is programmable. To compute with the device, you program it, inscribe the input on the tape, place the head over the square containing the leftmost input symbol, and set the machine in motion. Once the computation is completed, the machine will halt with the head positioned over the square containing the leftmost symbol of the output (or elsewhere if so programmed).

The Turing machine can perform six types of fundamental operations—read, write, move left, move right, change state, and halt. A complicated computation may consist of hundreds of thousands or even millions of such operations. Despite the Turing machine’s simplicity, it is capable of computing anything that any modern computer can compute.

A short definition of the thought experiment was given by Turing in his 1948 essay, Intelligent Machinery. Referring back to his 1936 publication, he writes that the Turing machine, here called a Logical Computing Machine, consisted of:
…an infinite memory capacity obtained in the form of an infinite tape marked out into squares on each of which a symbol could be printed. At any moment there is one symbol in the machine; it is called the scanned symbol. The machine can alter the scanned symbol and its behavior is in part determined by that symbol, but the symbols on the tape elsewhere do not affect the behavior of the machine. However, the tape can be moved back and forth through the machine, this being one of the elementary operations of the machine. Any symbol on the tape may therefore eventually have an innings.

Alan Turing played an important role in the creation of the first English electronic computers. During WWII, he worked for Britain’s codebreaking center (Government Code and Cypher School at Bletchley Park). He devised a number of techniques for breaking German ciphers, and together with Gordon Welchman developed an improved version of the Bomb—an electromechanical machine, that could find settings for the German Enigma coding machine. Later Turing devised a technique for use against the Lorenz cipher, used in the Germans’ new Geheimschreiber machine. In 1948, Turing and his colleague D. G. Champernowne wrote the first computer chess algorithm, called Turbochamp, but no computer to test it on.

Turing’s greatest contributions to the development of the digital computer are:
1. The idea of controlling the function of a computing machine by storing a program of symbolically, or numerically, encoded instructions in the machine’s memory.
2. His proof that, by this means, a single machine (a universal machine), is able to carry out every computation that can be carried out by any other Turing machine whatsoever. He stated: Electronic computers are intended to carry out any definite rule of thumb process which could have been done by a human operator working in a disciplined but unintelligent manner.

Norbert Wiener (1894–1964) was a remarkable man. He was born in Columbia, Missouri, in the American-Jewish family of Leo Wiener (1862–1939), of Lithuanian-Jewish origin, and Bertha Kahn (1867-1964) (German-Jewish). Norbert’s father Leo (born in Byelostok in Tsarist Russia and came to the USA in 1880) was an American historian, linguist, author, translator, and remarkable polyglot (Leo knew more than twenty languages). Since 1896 Leo taught at the cathedra of Slavic cultures at Harvard University and became the first American professor of Slavic literature.
The young Norbert was a child prodigy, educated at home by his father. After graduating from Ayer High School in 1906 at 11 years of age, Norbert entered Tufts College. He was awarded a BA in mathematics in 1909 at the age of 14, whereupon he began graduate studies in zoology at Harvard, obtaining a Ph.D. degree in 1912.

Later Wiener made significant contributions in mathematics, and pioneering contributions to electronic engineering, computer science, artificial intelligence, robotics, computer control, and automation. He is titled the father of cybernetics.

Wiener’s strangeness was proverbial in the scientist’s circles. Some people laugh at his somewhat baroque, short, rotund, and myopic figure, and his wanton and pompous speech, but in contrast to most of them, he shared his theories and findings with other researchers and credited the contributions of others. These included Soviet researchers and their findings (it was very dangerous and placed him under suspicion during the Cold War). He was a strong advocate of automation to improve the standard of living and overcome economic underdevelopment. He declined an invitation to join the Manhattan Project. After the war, he became increasingly concerned with what he saw as political interference in scientific research, and the militarization of science. His 1947 article “A Scientist Rebels” urged scientists to consider the ethical implications of their work. After the war, he refused to accept any government funding or work on military projects.

During World War II, Wiener worked on guided missile technology and studied how sophisticated electronics used the feedback principle, as when a missile changes its flight in response to its current position and direction. He noticed that the feedback principle is also a key feature of life forms from the simplest plants to the most complex animals, which change their actions in response to their environment. Wiener developed this concept into the field of cybernetics, concerning the combination of man and electronics, which he first published in his 1948 book Cybernetics.

Wiener’s vision of cybernetics had a powerful influence on later generations of scientists and inspired research into the potential to extend human capabilities with interfaces to sophisticated electronics, such as the user interface studies conducted by the SAGE program. Wiener changed the way everyone thought about computer technology, influencing several later developers of the Internet, most notably Licklider.

In his 1948 book and subsequent works, Wiener develops a theory of communication and control. He coins the term cybernetics (actually first known use of the term cybernetics was in an 1834 book by the great pioneer of electrical studies André-Marie Ampère, but he used it to refer to the study of peoples) to elaborate on the existing theory of the transmission of messages by incorporating his idea that people send messages within a system in an effort to control their surrounding environment. In his theory, Wiener compares humans to machines to illustrate how human communication is no different from the way machines function when given an order to complete a task. This is to say that when a human sends a message, they are only aware that it has been received once the recipient replies, either verbally or nonverbally. Additionally, he suggests that humans operate in a machine-like manner that is highly based on information processing and the constant desire to control our environment as well as the environment of those around us. According to Wiener:
… society can only be understood through a study of the messages and communication facilities which belong to it; and that in the future development of these messages and communication facilities, messages between man and machines, between machines and man, and between machine and machine, are destined to play an ever-increasing part.

The basic function of communication, which Wiener defines in his theory as the processing of information, is to control the environment in which one lives. Wiener asserts:
…information is a name for the content of what is exchanged with the outer world as we adjust to it, and make our adjustment felt upon it.

This idea suggests that the goal of human communication is to become familiarized with a certain environment while simultaneously influencing aspects of it. With this, Wiener wrote:
The purpose of Cybernetics is to develop a language and techniques that will enable us indeed to attack the problem of control and communication in general, but also to find the proper repertory of ideas and techniques to classify their particular manifestations under certain concepts.

Thus, he defines the problem with communication in terms of control and system malfunctions through the understanding of the Cybernetic theory.

One of the earliest functioning efforts in virtual reality was made in the late 1950s by the American cinematographer and inventor Morton Leonard Heilig (1926-1997). Heilig described his vision of a multi-sensory theater in a 1955 paper entitled “The Cinema of the Future”, but it took him several years to implement his ideas in practice.

The phrase “virtual reality” itself has been firstly used in the 1930s by the French poet, playwright, actor, and director Antonin Artaud (1896-1948). In 1938, working in Paris, Artaud published Le théâtre et son double, a collection of essays written in the early 1930s. In his book, Artaud described theatre as “la réalité virtuelle,” a virtual reality “in which characters, objects, and images take on the phantasmagoric force of alchemy’s visionary internal dramas.”

After writing his 1955 essay, Heilig set about creating the device he’d described, which aimed to stimulate four of the five senses: sight, hearing, smell, and touch. He even created his own 3D motion picture camera (see the nearby image) for capturing the short films that would be at the center of the experience. It was a side-by-side dual film 35mm camera and was small enough to be used as a hand-held device.

In 1957 Heilig applied for a patent for the first head-mounted display, called Telesphere Mask (see the patent of Telesphere Mask), and the patent was granted in 1960. The device featured stereoscopic 3D and wide vision with stereo sound. In January 1961 Heilig applied for Sensorama Simulator, and it was granted on 28 Aug. 1962 (see the patent of SENSORAMA). Using his own 3D camera, Heilig made five short films for Sensorama, including titles like Motorcycle, Belly Dancer, Dune Buggy, and, interestingly, I’m a Coca-Cola Bottle, all of which he shot, produced, and edited himself.

The Sensorama Simulator included a bucket seat for a single viewer (although his designs could be expanded for four), a set of handles, and viewing holes that were surrounded by a series of vents, which were sheltered under a hooded canopy to limit distraction. The 3D film was viewed through a set of ocular portals and filled a good portion of the user’s peripheral vision. The design even included an ultraviolet light to sanitize the viewing surface for the next user. In the Motorcycle movie, viewers would begin to feel the seat thrum as if astride a real vehicle, the handlebars would shake to the beat of the road, and the sounds of the engine and surroundings were delivered in full stereo. It was all first-person action, seen through the eyes of the driver as they navigated through the streets. The “reality” was further enhanced by a fan-generated breeze and a series of chemical scents, both emerging from the vents.

The Sensorama was initially considered for arcade use, but the machinery ended up being too complex. It had also been pitched to companies like Ford and International Harvester as a potential showroom display, but didn’t find any takers. Despite attracting the attention of the press at the time (see The Saturday Evening Port of 18 April 1964), it was difficult to find investors. Heilig did manage to find one, John Miller of White Plains, N.Y, an owner of a chain of department stores, and in 1963 they founded Sensorama Inc, but their efforts failed, leaving Sensorama stalled in the prototype stage.

Heilig continued to create variations on the theme and in 1966 he applied for a patent for his cinema-sized Experience Theater concept (see the patent of Experience Theater), in which he envisioned each seat as a type of Sensorama Simulator, except this time a special very large screen would fill a curved wall shared by all the viewers. Later Heilig developed a system called Thrillerama for the Walt Disney Company. It was a rear-projected 3-D motion picture system with live actors in front of the screen, interacting with the 3-D images on the screen.