chemigraphy

from The Century Dictionary.

• noun A process of making zinc etchings without the aid of photography.
• noun A process of obtaining halftones by printing, from the same plate, in two colors, or two shades of the same color, one of which is slightly out of register.

from the GNU version of the Collaborative International Dictionary of English.

• noun Any mechanical engraving process depending upon chemical action; specif., a process of zinc etching not employing photography.