Decisive Proof


At first atomism seemed like a perfect way to describe the laws of conservation of matter and definite proportions. But, just as it was becoming widely accepted, a Russian-German chemist named Friedrich Wilhelm Ostwald raised some doubts. To him, atoms were a clever idea, but lacked any physical proof. Ostwald insisted that there was no evidence that atoms really existed. He pointed out that scientists didn't even know how small (or big) atoms were, much less whether or not they were anything more than speculation.
Ostwald and the other doubters weren't satisfied until a little known German chemist and theorist published his own theories on atomic theory. His name was Albert Einstein, and his paper established without a doubt the existence of atoms. Einstein did this by examining a seemingly unrelated scientific discovery which had been made nearly a century before by Thomas Brown, a British botanist. While examining a grain of pollen floating on water, Brown noticed that it was randomly shaking about. The scientific community was puzzled by "Brownian Motion", but not very concerned. In 1905, Einstein proposed that this motion was caused by the random movement of the water particles.
Einstein worked out a complicated mathematical expression that involved the size of the pollen particle, the size of the water molecule, and other variables (Asimov 54). A French scientist, Jean Baptiste Perrin, took Einstein's equation and compared it with experimental data that he had carefully collected. According to the equation, the atoms in the water molecule were less than 1/10,000,000,000th of a meter across. After this, virtually every scientist was convinced that atoms were a reality, and not just a clever trick.


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