rik on Nostr: npub1zdp33…2vqv8 Do you go back far enough to recall the CHALK board analog: above ...

npub1zdp33shl69xr0uq3x8n5gsjykq9upycwh6nqm02c3f6x0frrn0dq42vqv8 (npub1zdp…vqv8) Do you go back far enough to recall the CHALK board analog: above the chalk board, in a roll-up along with drop down maps, was a piece of oil cloth with holes poked on a rectangular grid. The teacher would pull it down, RUN A CHALK ERASER OVER IT and it would auto-magically push chalk dust through the holes. when the oil cloth was rolled back up there'd be a lovely Cartesian grid!