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Steel engraving is a technique for printing illustrations based on steel instead of copper. It has been rarely used in artistic printmaking, although it was much used for reproductions in the 19th century. Steel engraving was introduced in 1792 by Jacob Perkins (1766–1849), an American inventor, for banknote printing. When Perkins moved to London in 1818, the technique was adapted in 1820 by Charles Warren and especially by Charles Heath (1785–1848) for Thomas Campbell's Pleasures of Hope, which contained the first published plates engraved on steel. The new technique only partially replaced the other commercial techniques of that time such as woodcut, wood engraving, copper engraving and later lithography. All the illustrations in the Encyclopædia Britannica of 1911 are steel engravings.
Most engraving is done by first laying out a broad, general outline onto the plate. This is commonly referred to as etching. After this step is complete the artist can move on to actually engraving the work. The tool most commonly used for engraving is the burin, which is a small bar of hardened steel with a sharp point. It is pushed along the plate to produce thin strips of waste metal and thin furrows. This action is followed by the use of a scraper to remove any burs, since they would be an impediment during the subsequent inking process. It is important to note that engraving must be done in the reverse or mirror image so that the image faces the correct way when the die prints. One trick of the trade was for engravers to look at the object that they were engraving through a mirror so that the image was naturally reversed and they would be less likely to engrave the image incorrectly. Steel plates can be case hardened to ensure that they can print thousands of times with little wear. Copper plates cannot be case hardened but can be steel-faced or nickel-plated to increase their life expectancy.
19th century 
Until around 1820 copper plates were the common medium used for engraving. Copper, being a soft metal, was easy to carve or engrave and the plates could be used to strike a few hundred copies before the image began to severely deteriorate from wear. Engravers then reworked a worn plate by retracing the previous engraving to sharpen the image again. Another advantage to using copper is that it is a soft metal and can be corrected or updated with a reasonable amount of effort. For this reason, copper plates were the preferred medium of printing for mapmakers, who needed to alter their maps whenever land was newly discovered, claimed, or changed hands.
During the 1820s steel began to replace copper as the preferred medium of commercial publishers for illustration, replacing etching but still rivaled by wood engraving and later lithography. Steel engraving produced plates with shaper, harder, more distinct lines. Also, the harder steel plates produced much longer wearing dies that could strike thousands of copies before they would need any repair or refurbishing engraving. The hardness of steel also allowed for much finer detail than would have been possible with copper, which would have quickly deteriorated under the resulting stress. As the nineteenth century began to close, devices such as the ruling machine made even greater detail possible, allowing for more exact parallel lines in very close proximity. Commercial etching techniques also gradually replaced steel engraving.
Steel engraving is still done today, but to a much lesser extent. Today, most printing is done using computerized stencils instead of a steel plate to transfer ink. An exception is currency, which is still printed using steel dies, since each bill then has a character and feel that is very difficult for counterfeiters to duplicate. An engraved plate causes the ink to be slightly raised and the paper to be slightly depressed, which produces a different haptic sensation than does paper printed by a stencil ink transfer process.
20th century 
By the beginning of the twentieth century, new tools made engraving much easier and more exact. One of these tools is the geometric lathe. The lathe is used to engrave images on plates, which are in turn engraved on rolls for such uses as printing bank notes. Another of these tools is the engraving machine. This machine uses a master template to lightly engrave a duplicate image which can be then engraved by hand or by the acid method. The machine also makes possible the reduction or enlargement of the letter for the duplicate image.
See also 
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Works cited 
- Bartrick, Steve. "Cooper & steel engraving explained". Retrieved 2008-09-21.
- Salade, Robert F. (1917). Plate Printing and Die Stamping. New York: Oswald Company.
- Allingham, Philip V. (2001-01-13). "The Technologies of Nineteenth-Century Illustration: Woodblock Engraving, Steel Engraving, and Other Processes". Victorian Web. Retrieved 2008-09-21.