Seeing is Believing

Relief printing is the oldest of the printed illustration processes. The woodcut, in which a knife is used on the plank side of a piece of wood to carve away everything except the lines to be printed, was invented in China during the eighth century, and reached Europe around 1400. With the invention of the printing press and movable type around 1455, the relief process, though tedious, became the primary means of printing illustrations in books, since the lines of the image stood up in relief in the same way as did the type, and they could be printed together on the same press. Early printers of scientific and medical books were quick to utilize the relief process, setting a precedent for those who followed.

The intaglio process, which appeared in the mid-fifteenth century, allowed the artist to produce the image directly instead of indirectly. Despite the fact that these illustrations could not be printed on the same press as text pages since they required much more pressure to print, by the seventeenth century intaglio had generally replaced the woodcut.

A method developed toward the end of the eighteenth century used engraving tools on the end grain of a hard wood, such as boxwood, to cut away the nonprinting surfaces while creating very fine details. This technique, which again allowed text and image to be printed together, led to an explosion of illustrated books, magazines, and newspapers beginning in the mid-nineteenth century. After the invention of photography, some wood engravers were able to mimic the appearance of a photograph. With the invention of the relief halftone process in the 1880s, printing blocks could be made directly from photographs, and wood engraving became obsolete for commercial publishing.