After the plates were printed, typically in black ink, color was added by hand.
Engraving is the art of incising lines, or designs, on a hard surface with a sharp tool.
The engraver must hold the engraving tool in one hand while moving the whole metal plate with the other. Long shallow lines, rather than short sharp cuts, are easiest to produce with this method. While a fairly stiff crisp image results, metal engraving allows a freer line than wood engraving. To become a proficient engraver, an apprentice had to serve some seven years. Etching, while similar to engraving, differs in that the plate is incised by acid rather than by a cutting tool.