Labels:bulletin board | sky | slide projector OCR: Plexiglas covering Pi ieces Block of five Roller launching fiush with last block of magncts soft irona ceramic magnets posi ion Plexialas coverina Track attached Brass under track to backing pooM Plexiglas Plexiglas trough to catch Horseshoe support 10r track rolier here or other end magnet Pieces maancts maanets position attoched bolts 5upport