This documentary starts with the theory as proposed by John Dalton in 1808, and outlines the progress made during the nineteenth century bringing in Faraday's early experiments in electrolysis, Mendeleeff's Periodic Table, and ending with ideas of the size of molecules and atoms then current. (Part 1 of 6)
| Directing | Derek Mayne | Director |
| Production | Frank Wells | Production Supervisor |
| Writing | J.V. Durden | Writer |
| Crew | Jack Parker | Cinematography |
| Crew | Kenneth Talbot | Cinematography |