At the end of the episode, Tankard tells George Warlweggan there's "not one atom of evidence" that Poldark committed murder. In Ancient Greece, they believed the world was made up of tiny things they called atoms. In the early 1800s chemist, John Dalton began to seriously study whether things were made up of tiny bits of matter. He named these tiny bits after the word first introduced by the ancients: atoms.