Let a beaker of liquid paraffin freeze. Cut through a block of ice with a wire loop that has a heavy mass hanging from it. A copper wire under tension cuts through a block of ice. A mass hanging from a loop of thin stainless steel wire cuts through a block of ice. The complexity of regelation is examined by Mark Zemansky.
Copper cuts through faster than iron or thread.
4C20.32 regelation H-57 Substances that expand on freezing show a lowering melting point under pressure. Two blocks of ice, held together by hand, will freeze. Also complete directions for the standard demo. Crushed ice squeezed in a thick walled cylinder forms a solid block. A letter disputing TPT 25,523 pointing out the difficulty in obtaining a uniform 0 C temperature in an ice bath.