Splash cloth is the most common name for a non-magic material used by alchemists to absorb alchemical spills and splatters, protecting whatever is underneath it. The continuous amount Alex has found is not uncommon at all; splash cloth is not generally used as cleanup rag or a small-scale protection device. Splash cloth is most commonly used to cover an entire lab and its contents, generally for experiments that require the alchemy department to call the dwarves in the mechanics department to wire up a contraption that can set off the reaction while the people conducting the experiment are standing in the safety of the hallway, typically behind more splash cloth.