In about 400 BCE, Democritus suggested that all matter is composed of tiny particles called atoms. Why then did it take until the nineteenth century for science to verify this? Part of the answer is that you can't see anything that small. Today, through the wonders of modern science, we have come to "see the invisible," and the atomic theory is the basis of nuclear physics. Actually, we don't see atoms today. We see images of them because they're...