Edison, Thomas Alva (1847-1931)

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EDISON, THOMAS ALVA (1847-1931)

Thomas Alva Edison was a master of combining ideas into working systems and overcoming technical hurdles that seemed insurmountable. He developed the notion of using teams of specialists in well-equipped laboratories to invent new devices. With the possible exception of the light-bulb, the inventions for which he was best known were in the field of communication.

Edison was born in Ohio; his father moved the family to Michigan when Thomas was seven years old. His father was looking for a town that would prosper in a country newly connected more by railroads than canals. It was on the new railroad lines in Edison's early teenage years that he first became entranced with communication technology.

In addition to selling newspapers on the trains, Edison began to print his own railroad newspaper called the Weekly Herald. He gathered some of his news stories from reports coming over the railroad telegraphs. At the age of fifteen, he was taught telegraphy by a railroad stationmaster and soon began to experiment with modifications to the telegraph itself. He worked on systems to send multiple messages simultaneously over the telegraph and on automatic telegraphy. During this work, he even reported finding electromagnetic waves, though he did not know what this "etheric force" was and took the discovery no further than reporting it. Other work on the telegraph led to the invention of the mimeograph machine and to improvements to the telephone.

In 1877, Edison discovered that it was possible to record sound, and this had a dramatic effect on the future of communication. He first developed a paraffin paper strip that would pass under a needle, much like a magnetic tape slides across a magnet in a modern tape recorder. This "telephonic repeater" recorded crude sounds of voices. From this, he began work on his first phonograph. Edison sketched out a crude design for a working phonograph recorder and gave the assignment to make the device to John Kruesi, one of his workmen. About a week later, the finished device, which placed grooves in tin-foil wrapped around a drum, recorded human voices on the very first try. Edison also made a disc model that used tin-foil to record sounds, but he soon set aside the phonograph to work on the electric lightbulb.

Ten years later, Edison made his next major improvement on the phonograph when he developed a solid wax cylinder that replaced the tin-foil medium for recording. He developed "The Improved Edison Phonograph" and then "The Perfected Edison Phonograph" machines. Edison sold the Edison Phonograph Company for $500,000 in 1887 to the North American Phonograph Company, which immediately began employing the devices in business for dictation purposes. Edison continued to work on development of the phonograph, however, under a company named Edison Phonograph Works. This company produced talking dolls and musical cylinders for entertainment. Initially, there was no way to reproduce (or duplicate) a cylinder; each recording was an original. However, methods of limited mechanical reproduction were soon devised, and Edison eventually developed a method of reproduction in 1898 that used a molded wax cylinder—enabling the mass production of individual recordings. Edison also developed electronic and spring-wound versions of the phonograph for business and home use, respectively. Most of the recordings lasted two minutes each, and the spring-wound phonographs could play up to six cylinders without being rewound.

Edison was not the only person working in this area by the end of the nineteenth century; he had plenty of competition from other phonograph companies. The North American Phonograph Company had granted territories to franchisees for selling phonograph equipment. One of these was the Columbia Phonograph Company, which developed many versions of phonographs to compete directly against those designed by Edison. Columbia and several other companies also produced many of their own musical cylinders. In particular, Emile Berliner created a flat, hard shellac disc that had better sound quality and could be stored more easily than a wax cylinder. This development, adopted by the Victor Talking Machine Company, eventually replaced the Edison cylinder as the dominant version of the phonograph.

During much of the time that Edison was working on the phonograph, he was also developing another major invention, or rather series of inventions, that would dramatically influence the future of communication. With no background in photography, Edison plunged into the study of how to capture and use a rapid series of pictures to approximate live motion. He encouraged George Eastman to adapt his photographic process so that it could be used on flexible film, which could then be used for Edison's idea of approximating motion with a series of pictures. Following Eastman's success, Edison developed and patented in 1893 the Kinetograph, a camera that could capture a rapid sequence of pictures on flexible film that was perforated at the edge. Laboratory assistant William Dickson was his chief assistant on the project. While others, such as Eadweard Muybridge, had captured a short series of pictures using multiple cameras and had played them back as a repeating sequence, Edison's camera was more practical, so it provided a leap forward in the field.

His camera was followed by the invention of the Kinetoscope, a one-person machine that allowed fifty feet of film to loop continuously through a viewing device that magnified the image for the patron. For a nickel, patrons could watch the simple acts of gymnasts, jugglers, and acrobats who had performed for the cameras in Edison's Black Maria film studio. The studio was built on a revolving platform with a roof that opened to allow the sunlight in so the scene could be illuminated effectively. Large numbers of these films were made for use in the Kinetoscope machines, but most of them have been lost to posterity because he failed to copyright the ones made before 1896. Copyrighting films required the deposit of a print on paper in the U.S. Copyright office, thus providing a record of the film on a permanent medium, while early filmstock allowed the images to fade away with time. At one point, Edison linked the Kinetoscope to the phonograph, thereby creating an early version of talking pictures, but this innovation did not catch on for general use.

The Kinetoscope, which limited viewing to one person at a time, finally gave way to Edison's more refined 1896 invention of the Vitascope, a projector that used an arc lamp to light up the photographs and project them onto a screen— thereby allowing multiple viewers to see the images at the same time. The Vitascope drew the film in intermittent jumps in front of a rapidly opening and closing shutter. Each time the film paused, the shutter allowed a burst of light through the opening, thereby projecting one frame of the film. When the image changed at a rapid rate, such as forty-eight frames per second (the standard speed that is used in modern motion pictures), the human eye was unable to detect the momentary gap between the images. Therefore, because of this phenomenon (called "persistence of vision"), the constant barrage of pictures in rapid succession fooled the eye into seeing constant motion.

Beyond the development of the mechanical elements of motion pictures, Edison's employees also advanced the art of motion pictures, conceiving elements of story, editing, cross-cutting, and moving the camera. However, Edison's own contribution basically ended at the mechanical operation of the machinery. He left it to others to pursue the art of motion pictures.