Close-up of the same board-formed reinforced-concrete surface in the vault-adjacent space at the Hoffmann-Hayman factory, photographed 5 October 2014 (Sony DSC-RX100) — seconds after the WATCH YOUR HEAD frame — showing horizontal formwork grain, light tan-grey paste with fine pitting and white speckle, and a handwritten inscription in dark graphite or ink reading the name **Daniel Ruiz** on a diagonal above a short date line **3-15-01** (most naturally read as 15 March 2001 in U.S. month-day-year order), a worker or visitor mark on the 1930s cast concrete
