Olivier Bernier (“American Made,” December 1988) obviously needs to review the printing processes. He calls lithography “the making of prints through the use of engraved stones,” but even the most lowly printer’s devil should know that lithography (or planography) by definition is the process of printing from a flat surface.

Mr. Bernier got one part of the process correct—“the image is drawn with a grease pencil.” From there he went awry and jumped from lithography to relief printing, which is printing from a raised surface. In lithography, after the image is drawn, water is applied, which does not adhere to the greasy image. Next, oily ink is applied, which does not mix with the water. The resulting print shows only the original details drawn with the grease pencil.

To complete the lesson, the third type of printing is intaglio, or printing from an engraved or sunken image. The Treasury Department uses intaglio to print currency.