This medium was developed on Cape Cod early in this century making it the only truly American art form. It is a means by which a printmaker can create color prints using a single block of wood (unlike traditional Japanese prints, which require a separate block for each color).

Once a design for a print has been created it is drawn on a wooden block, usually made of white pine. These drawn lines are then cut out from the block to a minimum depth of 1/16 of an inch using a sharp blade. The resulting incised lines serve as boundaries between areas of different color when the block is inked and, because they are below the surface of the block and receive no color, appear as ‘white lines’ in the completed print. Hence, the name of the medium.

The printing process is begun by clamping a sheet of hand-made Japanese printmaking paper to the block, ensuring accurate registration. Each color is then applied to the block with a brush and printed separately. The process, though made somewhat simpler because of the use of a single block, is a slow one. Consequently, the number of individual prints in an edition is usually very small.