Tuesday, March 20, 2007

Printing press

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For the invention and technology of movable type, see Movable type
Printing press from 1811, photographed in Munich, Germany.
Printing press from 1811, photographed in Munich, Germany.

The printing press is a chemical printing device for making copies of identical text on multiple sheets of paper. It was invented in Germany by the goldsmith and printer Johannes Gutenberg in 1445. Printing methods based on Gutenberg's printing press spread rapidly throughout first Europe and then the rest of the world, replacing most block printing and making it the sole progenitor of modern movable type printing. Printing's effect on civilization has often been discussed in terms of the effect of the "printing press" on civilization—a rhetorical device, which alludes to the pivotal role of the printing press in the global spread of printing.

Movable type printing, which allowed individual characters to be arranged to form words, is a separate invention from the printing press. In what is regarded as an independent invention, movable type printing as we know it today was invented in Germany by Gutenberg in the 1440s, although the first known invention was in China by Bi Sheng between 1041 and 1048.

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[edit] Invention of the printing press

Johannes Gutenberg is credited with inventing the first printing press, although there are several local claims for the invention of the printing press in other parts of Europe, including Laurens Janszoon Coster in the Netherlands and Panfilo Castaldi in Italy. Screw presses for olives and wine were known in Europe since Roman times; presses for the binding of manuscript books were also in use. Gutenberg was the first to convert the concept for printing uses. Gutenberg's use of mechanical presses, along with other innovations of his, made printing from the start a proto-industrial process with a far greater printing output than with manual work.

Having previously worked as a professional goldsmith, Gutenberg also made skillful use of the knowledge of metals he had learned as a craftsman. He was the first to make his type from an alloy of lead, tin, and antimony, which was critical for producing durable type that produced high-quality printed books, and proved to be more suitable for printing than the clay, wooden or bronze types used in East Asia. To create these lead types, Gutenberg used what some considered his most ingenious invention, a special matrix enabling the moulding of new movable types at short notice and with unprecedented precision.

In the Gutenberg Bible, Gutenberg made a trial of coloured printing for a few of the page headings, present only in some copies. (Albert Kapr, "Johannes Gutenberg", Scolar 1996, p. 172)

For more details on this topic, see Gutenberg Bible.

A later work, the Mainz Psalter of 1453, presumably designed by Gutenberg but published under the imprint of his successors Johann Fust and Peter Schoeffer, had elaborate red and blue printed initials. (Kapr, p.203). Gutenberg is also credited with the introduction of an oil-based ink which was more durable than the previously used water-based inks. As printing material he used both vellum and paper, the latter having been introduced in Europe somewhat earlier from China by way of the Arabs, who had a paper mill in operation in Baghdad as early as 794.

[edit] Method of using the Gutenberg-style printing press

Adapted from Philip Gaskell, A New Introduction to Bibliography (Oxford: OUP, 1995)

The parts of the printing press:

  • The frame - immovably braces and supports the two moving parts.
  • The carriage assembly - carries the type and paper in and out of the impression assembly.
  • The impression assembly - pushes (or presses) the paper onto the inked type.

The printing process:

  1. Buy the paper. Paper from the same lot will give the resulting book a uniform look.
  2. Arrange the paper into stacks of 250 sheets. These are called tokens and are the units for calculating a pressman’s work. Most book editions are in multiples of 250 copies.
  3. The night before printing, wet the stack of paper and let it stand under a heavy weight. This helps the paper to absorb ink.
  4. Make register by loading the forme into the carriage assembly on the press stone so that when the paper was printed on one side and then flipped over and printed on the other side, the pages printed squarely on top of each other. Press points on the tympan were adjusted to hold the paper in position.
  5. Paste one sheet of paper to the tympan to serve as a guide to positioning the sheets of paper to be printed.
  6. Paste another sheet of paper to the frisket, print the first forme on it and cut out the areas where text appears. This will protect the white areas of the sheet from dirt and ink.
  7. The beater inks the type in the forme (called beating the forme) using two ink balls - leather-covered pads of horsehair or wool with handles. Ink rollers were not invented until after the hand-press era.
  8. The puller lays the sheet of clean paper to be printed onto the tympan and then lowers the frisket onto it.
  9. The beater folds the tympan, paper, and frisket down onto the forme.
  10. The puller runs the front end of the carriage assembly under the impression assembly by turning the rounce.
  11. The puller pulls on the bar to force the platen down onto the tympan, thereby pressing the paper onto the inked forme. When he releases the bar, the platen will spring back.
  12. The rounce is turned again to pull the second half of the forme under the platen and the platen is lowered again.
  13. Release the bar to lift the platen and turn the rounce to pull the carriage assembly out from under the impression assembly.
  14. Unfold the carriage assembly to remove the printed sheet.
  15. Repeat this procedure from step 8 for each sheet in the stack.

The same procedure was followed for printing the second side of the sheet, positioning the sheet on the already-adjusted points. Printing the second side is called perfecting. In the sixteenth century, the first side of the sheet was printed in the morning and the second side was printed in the afternoon. In the eighteenth century, one side was done on one press and the other side was done on another press.

Two pressmen could print 250 sheets an hour, going from step 8 to step 15 in about fifteen seconds but according to McKenzie, they seldom did. A full press-crew was two men - a puller and a beater, and often a boy to put on fresh ink.

[edit] Impact of printing

[edit] Effects of printing on culture

The impact of printing is comparable to the development of writing and the invention of the alphabet or the internet, as far as its effects on the society. Printing did not achieve a position of total dominance, and handwritten manuscripts continued to be produced, and the continuing influences of the printed word and oral communication on each other meant that no one form of communication could dominate.

Printing also was a factor in the establishment of a community of scientists who could easily communicate their discoveries, which had previously been communicated by personal letters, helping to bring on the scientific revolution. Also, although early texts were printed in Latin, books were soon produced in common European vernaculars, leading over several centuries to the decline of the Latin language as the medium of scholarly communication.

Because of the printing press, authorship became more meaningful and profitable. It was suddenly important who had said or written what, and what the precise formulation and time of composition was. This allowed the exact citing of references, producing the rule, "One Author, one work (title), one piece of information" (Giesecke, 1989; 325). Before, the author was less important, since a copy of Aristotle made in Paris would not be exactly identical to one made in Bologna. For many works prior to the printing press, the name of the author was entirely lost.

Because the printing process ensured that the same information fell on the same pages, page numbering, tables of contents, and indices became common, though they previously had not been unknown. The process of reading was also changed, gradually changing over several centuries from oral readings to silent, private reading. And obviously, the availability of printed materials led to a continuing rise in the literacy level, revolutionizing education.

It can also be argued that printing changed the way Europeans thought. With the older illuminated manuscripts, the immediate visual emphasis was on the images and the beauty of the page. Early printed works emphasized principally the text and the line of argument. In the sciences, the introduction of the printing press marked a move from the medieval language of metaphors to the adoption of the scientific method.[citation needed]

In general, knowledge came closer to the hands of the people, since printed books could be sold for a fraction of the cost of illuminated manuscripts. There were also more copies of each book available, so that more people could discuss them. Within 50-60 years, the entire library of "classical" knowledge had been printed on the new presses (Eisenstein, 1969; 52). The spread of works also led to the creation of copies by other parties than the original author, leading to the formulation of copyright laws. Furthermore, as the books spread into the hands of the people, Latin was gradually replaced by the national languages. This development was one of the keys to the creation of modern nations.

Some theorists, such as McLuhan, Eisenstein, Kittler, and Giesecke, see an "alphabetic monopoly" as having developed from printing, removing the role of the image from society. Other authors stress that printed works themselves are a visual medium. Certainly, modern developments in printing have revitalized the role of illustrations.

[edit] The art of book printing

For years, book printing was considered a true art form. Typesetting, or the placement of the characters on the page, including the use of ligatures, was passed down from master to apprentice. In Germany, the art of typesetting was termed the "black art" in allusion to the ink-covered printers. It has largely been replaced by computer typesetting programs, which make it possible to get similar results with less human involvement. Some practitioners continue to print books the way Gutenberg did. For example, there is a yearly convention of traditional book printers in Mainz, Germany.

[edit] Printing in the industrial age

The Gutenberg press was much more efficient than manual copying, and as testament to its effectiveness, it was essentially unchanged from the time of its invention until the Industrial Revolution, some three hundred years later. The "old style" press (as it was termed in the nineteenth century) was constructed of wood and could produce 240 impressions per hour of simple work using a well experienced two-man crew.

The invention of the steam powered press, credited to the German inventors Friedrich Koenig and Andreas Friedrich Bauer in 1812, made it possible to print over a thousand copies of a page per hour.

Koenig and Bauer sold two of their first models to The Times in London in 1814, capable of 1,100 impressions per hour. The first edition so printed was on November 28, 1814. They went on to perfect the early model so that it could print on both sides of a sheet at once. This began the long process of making newspapers available to a mass audience (which in turn helped spread literacy), and from the 1820s changed the nature of book production, forcing a greater standardization in titles and other metadata. Their company Koenig & Bauer AG is still one of the world's largest manufacturers of printing presses today.

Diagram of a single-side printing press c.1820

Their press was improved by Applegath and Cooper. The diagram indicates the principle of operation of a Cooper and Applegath's Single Machine. The press is built up from a large flat inking table (A) which moves regularly back and forth, the form (B) on the table holds the type. The paper travels clockwise round a large cloth covered cylinder, the impression roller (C), and is pressed against the table. The ductor roller (D) rotates and so draws ink from the attached reservoir. The ink passes from the ductor roller to the vibrating roller (E), this moves, on its arms, in a regular motion between the ductor roller and the table. The ink is spread thinly and evenly by the distributing rollers (F) and then, as the table moves, passes onto the inking rollers (G). The axles of the inking rollers rest in grooves, allowing them to rise and fall, they are also position at a slight angle to the table to improve ink distribution. As the table continues to move the form passes alternately under the inking rollers, twice, and then under the impression roller.

Later on in the middle of the 19th century the rotary printing press (invented in 1833 in the United States by Richard M. Hoe) allowed millions of copies of a page in a single day. Mass production of printed works flourished after the transition to rolled paper, as continuous feed allowed the presses to run at a much faster pace.

Also, in the middle of the 19th century, there was a separate development of jobbing presses, small presses capable of printing small-format pieces such as billheads, letterheads, business cards, and envelopes. Jobbing presses were capable of quick set-up (average makeready time for a small job was under 15 minutes) and quick production (even on treadle-powered jobbing presses it was considered normal to get 1,000 impressions per hour [iph] with one pressman, with speeds of 1,500 iph often attained on simple envelope work). Job printing emerged as a reasonably cost-effective duplicating solution for commerce at this time.

Later inventions in this field include the following:

[edit] References

  • Fontaine, Jean-Paul. L'aventure du livre: Du manuscrit medieval a nos jours. Paris: Bibliotheque de l'image, 1999.
  • Citation from The Encyclopedia of World History Sixth Edition, Peter N. Stearns (general editor), © 2001 The Houghton Mifflin Company, at Bartleby.com.

[edit] See also

[edit] External links

  • BGDP Safety on printing presses

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