Typewriter, machine designed to print or impress type characters on paper, as a speedier and more legible substitute for handwriting (see Printing; Writing Implements). Since the introduction of practical typewriters in the 1870s, the machines have come into universal use and have played an important part in the development of modern business and in the great dissemination of written and printed information that has characterized the 20th century. See Office Systems.
II. Early Typewriters
The first recorded attempt to produce a writing machine was made by the British inventor Henry Mill, who obtained a British patent on such a machine in 1714. The next patent issued for a typewriter was granted to the American inventor William Austin Burt in 1829 for a machine with type arranged on a semicircular wheel that was revolved to the desired letter, then pressed against the paper. In 1833 a French patent was given to the French inventor Xavier Progin for a machine that embodied for the first time one of the principles employed in modern typewriters: the use for each letter or symbol of separate typebars, actuated by separate lever keys.
The device used for moving the paper between letters and between lines on almost all modern typewriters is a cylindrical platen, against which the paper is held firmly. The platen moves horizontally to produce the spacing between lines. The first machine to use this method of spacing was made in 1843 by the American inventor Charles Grover Thurber. The printing portion of his typewriter was a metal ring that revolved horizontally above the platen and was equipped with a series of vertical keys or plungers having pieces of type at the bottom. The machine was operated by revolving the wheel until the correct letter was centered over the printing position on the platen, and then striking the key.
Several other inventors attempted to produce machines designed to make embossed impressions that could be read by the blind. One such machine, developed by the American inventor Alfred Ely Beach in 1856, resembled the modern typewriter in the arrangement of its keys and typebars, but embossed its letters on a narrow paper strip instead of a sheet. A similar machine created by the American inventor Samuel W. Francis, and patented by him in 1856, had a circular arrangement of typebars, a moving paper holder, a bell that rang to signal the end of a line, and an inked ribbon. The keyboard arrangement of Francis's machine resembled the black and white keys of a piano.
III. The Remington Typewriter
During the 1850s and '60s many inventors tried to produce a workable typewriter, but none succeeded until 1868, when three American inventors, Christopher Latham Sholes, Carlos Glidden, and Samuel W. Soulé, patented a writing machine. Early in 1873 they contracted with E. Remington & Sons of Ilion, New York, manufacturers of rifles and sewing machines, to produce their typewriter. The first Remington typewriter produced for Sholes and Glidden came off the line in September 1873.
The Remington incorporated almost all the essential features of the modern machine. The paper was held in a carriage between a rubber platen and a smaller rubber cylinder, which were set parallel to one another. The carriage was moved from right to left by means of a spring as the letters were struck; the movement was regulated by an escapement mechanism, so that the carriage traveled the distance of one space for each letter. The carriage was returned to the right by a lever, which also served to revolve the platen for a space of one line by means of a ratchet and pawl. The typebars were arranged in a circle; when any one of the keys, which were arranged in a banked keyboard at the front of the machine, was depressed, the corresponding typebar struck against the bottom of the platen by lever action. An inked cloth ribbon ran between the typebar and the platen, and the type struck this ribbon to make an inked impression on the underlying paper that was held against the platen above the ribbon. The ribbon was carried on a pair of spools and was moved automatically after each impression.
The early Remingtons wrote only in capital letters, but in 1878 the carriage shift was made possible by two inventions. One was a key and lever that moved the carriage a short distance down for printing the capitals, and another key and lever that moved the carriage to its original position for printing the lowercase, or small, letters. The other was the double key, with capital and lowercase letters mounted on the same typebars. The introduction of the shift and double keying permitted the addition of numbers and other symbols without increasing the size of the keyboard. The typing technique known as touch-typing, which enabled operators to achieve great speed and accuracy, soon appeared.
Typebars of early commercial typewriters struck the paper at the bottom of the platen; the line being written was thus not visible to the operator. Beginning in the early 1880s this disadvantage was eliminated by the so-called visible typewriters, in which the type struck the front of the platen.
Following the success of the Sholes-Glidden-Remington machine, many new models of typewriters were invented, but few of them proved to be of any enduring worth, and most were discarded. Among the typewriters that proved successful in the U.S. were the Underwood, L. C. Smith, Royal, and Woodstock.
Two entirely different designs of typewriter that did not use the typebar system were also introduced in the U.S. during the 1880s and '90s. One of these was the so-called type-wheel typewriter, typified by the Blickensderfer machine. In this typewriter all the typefaces were mounted on the outside of a single small cylinder that was revolved and moved up and down by the action of the keys to place the proper letter in the typing space. The Hammond typewriter, first introduced in 1880, worked on a somewhat similar principle and carried its type on interchangeable, curved shuttles fixed to the outside of a metal ring. In both these machines no platens were used, and the type did not strike against the paper to make an impression. Instead, the paper was held in a vertical position, unsupported by a platen, and the impression was made by a hammer that struck the back of the paper, forcing it against the ribbon and the type. The advantage of the Hammond machine was the interchangeability of type shuttles, making possible the use of a variety of typefaces on the same machine.
Small portable typewriters working on the typebar principle were first introduced in 1912. The smallest of modern portable typewriters are no larger than an unabridged dictionary and offer most of the features of full-sized office machines. Noiseless typewriters, which came into use after World War I, used a lever system for actuating the typebars, but relied on pressure rather than a striking motion to make the type impression, reducing the noise of operation.
IV. Electric Typewriters
Electric typewriters have been in extensive use since 1925, and a major role in the field has been played by the International Business Machines Corporation (IBM). In these machines a motor-driven mechanism performs the actual work of lifting the typebar and striking it against the ribbon, and also of returning the carriage to the right and turning the platen at the end of the line. Because the keys are used only to start the electric mechanism, the pressure used by the operator is much less than on conventional mechanical typewriters, and as a result the operator can type faster and with less fatigue. Another important advantage is that the impress, or pressure, of each letter is completely uniform.
Electric typewriters are available that permit swift correction of mistakes; that automatically justify, or evenly align, the right-hand margin; that supply characters in foreign languages and alphabets; that type certain words at a single stroke; that have ribbons yielding uniform, unfading letters; and that are equipped with interchangeable type spheres that supply a variety of typefaces, such as italic or cursive.
V. Recent Developments
The application of electronic controls made possible by the microprocessor and computer storage have multiplied the uses of the modern typewriter, transforming it into a word processor or data processor. The connection of a specially designed electronic typewriter keyboard to computer logic and memory circuits permits the assembled system to perform such automatic functions as producing a number of copies of a given letter to different people, with appropriate alterations within the body of the letter.
Typewriter composing machines operating as computer terminals now prepare copy for printing, proportionally spacing characters and automatically justifying the margins. The information typed can be edited on a cathode-ray screen. In the 1970s and '80s many newspapers and other print media equipped their writers and editors with such machines. These and other high-speed printing and data-processing machines make use of the typewriter keyboardstill in the form designed by Christopher Sholesbut they are actually extensions of computer rather than typewriter technology. See Microcomputer.
HOW TO CITE THIS ARTICLE
"Typewriter," Microsoft® Encarta® Online Encyclopedia 2000
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