Most people in 1940 exalted the big with a positive mania for admiring the newest biggest hydro dam or heavy bomber and they considered an atom to be pretty tiny - in fact, probably the tiniest thing in the Universe.
But even in 1940, scientists and those who kept up with popular media reports of the latest scientific discoveries and theories knew that that rocky objects like the Earth, made up of atoms combined into compounds and mixtures, were a blindingly small part of the Universe.