Ginsberg places a room-temperature block of clear glass in a C-clamp and slowly tightens it, filming between two crossed polarizing filters. To the naked eye, the block stays transparent and unchanged. Through the filters, fields of color bloom across it and grow more intricate as the force increases. Glass feels rigid, yet under pressure it deforms elastically, and that hidden strain alters the light passing through it, an effect called stress-induced birefringence. Force that would normally register only as resistance, or as a crack, becomes an image. The glass acts as an instrument, revealing a response present all along.