One of the oldest yet interesting experiments related to heat and thermodynamics is placing a string on a block of ice and hanging two masses from the ends of the string. Sometime later, it is discovered that the string has passed through the ice without cutting it in half. A simple explanation of this effect is that the pressure caused by the string makes the ice melt just below the string, the string slides down, and the water freezes again just above the string. This phenomenon, however, is interesting and puzzling enough for many curious science students that it deserves a more detailed and quantitative explanation.