Most of us can remember the first time we heard or read something which seemed to throw a new light upon the world. In my own case, it comes back with extreme clarity. I was a child of eight or nine, and I had got hold of a bound volume of Arthur Mee’s Children’s Encyclopaedia. It was a dark afternoon, and I was sitting by the fire. Suddenly, for the first time, I ran across an account of how atoms were supposed to be built up. The article had been written before Rutherford had discovered the nucleus, although by the time I read it the nuclear atom must have been well known. However, I was innocent of all that, I had never seen the word ‘atom’ before; this article – it was quite short and was contained, I think, in a section called the Child’s Book of Wonder – explained that its descriptions were only a guess, that no man knew the truth, and yet it seemed to open up a new sight of the world.
It told me that if you could go on cutting up any sort of material, you would arrive at atoms in the end. These atoms were so small that no one would ever see them and you could crowd countless millions on to a pin point. There were different sorts of atoms: and yet, if you cut up the atoms themselves, you found in some mysterious way that they were made of the same stuff. That idea probably came more easily to a child than to an adult, and I swallowed it whole.
The actual description of these atoms was rather quaint, in the light of later knowledge. Small as they were, they were packed with much smaller things called electrons (which, of course, had been known about since J J Thomson’s work in the nineties). According to the article, these electrons were like tennis balls in a cathedral; and, again according to the article, the tennis balls were in violent and random motion across the interior of the cathedral. It is a little difficult nowadays to see how that picture was ever conceived; I found it very easy to unlearn a few years later.
Yet, though so much of that article could not endure, it gave me the first sharp mental excitement I ever had. Somehow it gave me the heightened sense of thinking and imagining at the same time. And one is lucky if those exalted moments visit one more than ten or twenty times in a whole life…
Taken from ‘The First Excitement that Knowledge Gives’: editorial by the author in Discovery, April 1939