Blackboards, the legend goes, were invented by a teacher. In the mid-19th century, James Pillans was headmaster of the Royal High School in Edinburgh, Scotland. Teaching geography, he found himself in need of a device that would allow him to share visual information with all his students, simultaneously — a more theatrical and efficient version of the slates students used to write their lessons at their desks. Pillans had chalk; he had tablets. Then he had an idea.
Today, in an age of dry-erase whiteboards and write-on wall paint — an age that has produced surfaces and markers that allow writings to be undone with the ruthless efficiency of a single swipe — blackboards have taken on the wistfulness of the outmoded technology. And the semi-erased chalkboard, in particular — its darkness swirled with the detritus of unknown decisions and revisions — compounds the nostalgia. Its spectral insights mingle in the bright dust of calcium carbonate.