Archimedes Discovers How to Measure Volume

Hieron asked Archimedes to discover, without damaging it, whether a certain crown or wreath was made of pure gold, or if the goldsmith had fraudulently alloyed it with some baser metal. While Archimedes was turning the problem over in his mind, he chanced to be in the bath house. There, as he was sitting in the bath, he noticed that the amount of water that was flowing over the top of it was equal in volume to that part of his body that was immersed. He saw at once a way of solving the proble...

 The Unique Properties of Ice

By the standard of other substances, the properties of ice are bizarre, yet ice is so perfectly suited to our purpose that if it didn't exist we should have to invent it. With few exceptions, the solid phase of matter is more dense than the liquid phase; water. alone among common substances, violates the rule. As water begins to cool, it first contracts and becomes more dense, in the typical way. But about four degrees above the freezing point, something peculiar happens. It ceases to contrac...