Steel engraving

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.

Confusingly, the printmaking technique used in steel engravings is, after the earliest years in the 1820s, normally a combination of etching and true engraving, with etching becoming dominant in later examples, after the technique became popular in the 1830s. Engraving is done with a burin, which is a small bar of hardened steel with a sharp point. It is pushed along the plate to produce thin furrowed lines, leaving "burr" or strips of waste metal to the side. This is followed by the use of a scraper to remove any burs, since they would be an impediment during the subsequent inking process. Steel plates are very hard for this technique, which is normally used on softer copper plates. So steel engraving also used etching (q.v.), where acid creates the lines in the plates in the pattern made by selectively removing a thin coating of acid-resistant ground by tools. This is much less effort. As well as etching needles, the etched part of steel engravings made great use of roulettes, small wheels mounted in handles which have regular sharp projections which produce broken lines of dots and dashes when rolled across the plate. Roulettes of different types were used together with the burin and needle to create densely packed marks which appear as tonal to the eye, and allow a great variety of textures and effects. True burin engraving was generally used to finish the etched image.

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