Atom: Journey Across the Subatomic Cosmos is a non-fiction book by Isaac Asimov. It was initially published on May 31, 1991, by Dutton Adult.
In it, Asimov presents the atom and subatomic particles in a historical context, beginning with Democritus's original thought experiments and theory of atomism, and ending with then-current knowledge of the fundamental particles.
The book is separated into twelve chapters, plus the index.