In the early 1960s Roth developed a visual system consisting of twenty-three images, each of which corresponds to one or two letters of the alphabet. The artist had a set of rubber stamps made from his sketches, which he used to produce about three hundred stamp drawings. Many of these are reproduced in this 1967 book, along with a key indicating which symbol corresponds to which letter of the alphabet, as well as additional writings and illustrations by Roth. The drawings could, in theory, be read as texts; however, Roth intentionally complicated their legibility by layering stamps on top of one another and asserting that each symbol had varying meanings, depending on the orientation in which it was stamped.