In 1970 Cornell doctoral student Harold D. Craft Jr. stacked 80 consecutive radio pulses from pulsar CP1919 into a single ridge-line plot, front waves occluding those behind — a data figure buried in a PhD thesis. Nine years later Peter Saville lifted it, inverted it to white-on-black, and stamped it on Joy Division's Unknown Pleasures. This system is that totem: pure white line on true black, vast negative space, no ornament — pure signal.