Please Don't Get Relegated

X is the phenomenon of melting under pressure and freezing again when the pressure is reduced. Many textbooks and reference books as well as websites often claim that X can be demonstrated by looping a fine wire around a block of ice , with a heavy weight attached to it. The pressure exerted on the ice slowly melts it locally, permitting the wire to pass through the entire block. The wire's track will refill as soon as pressure is relieved, so the ice block will remain solid even after wire passes completely through.

X was discovered by Y and occurs only for substances that have the property of expanding upon freezing, for the melting points of those substances decrease with increasing external pressure.