Zitat des Tages von William Henry Bragg:
When a liquid boils, the temperature has been raised to such a pitch that the evaporating molecules are sufficient in number and speed to lift off the air from the surface of the liquid and push it back en masse.
The atoms may be compared to the letters of the alphabet, which can be put together into innumerable ways to form words. So the atoms are combined in equal variety to form what are called molecules.
Let us think of Nature as a builder, making all that we see out of atoms of a limited number of kinds, just as the builder of a house constructs it out of so many different kinds of things: bricks, slates, planks, panes of glass, and so on.
Sound is a movement which is handed on from atom to atom in a gas through which the sound is passing, just as a chain of workers pass buckets of water to a fire. The quicker the workers move their hands and arms, the quicker the water moves.
