Take a small slab of ice, a thin wire, two identical weights.
In the above experiment, the wire moves through the ice slab. However, the ice slab does not break. Why ?

Explanation

When the thin wire with two equal weights attached to its ends is hung over the block of ice, it exerts pressure on the ice below it. Due to this, the melting point of ice below the wire is lowered and some ice melts. The wire passes through the water so formed. The water above the wire is no longer under pressure and, therefore,refreezes. Once again the ice below the wire melts, and the wire passes through it, and the process continues. In this way, due to alternate melting of ice and refreezing of water, the wire cuts right through the block of ice leaving the block intact.