The London Tube map is a diagram, not a geographical map. Before the 1930s the network was run by separate companies, and their maps were simply lines drawn over ordinary street maps. Harry Beck, a London Underground employee, realised that because trains ran underground, passengers only needed to know the order of stations and where lines connected, not true distances or positions. He produced a schematic map using straight lines at horizontal, vertical or 45-degree angles, with interchange stations marked separately, and it was first published in 1933. It was popular immediately, and the Underground has used diagrams like it ever since.

In 1909 D. W. Griffith made a 14-minute film about a speculator who corners the wheat market and doubles the price of bread. A farmer sows his field while a 'Wheat King' gambles in the Chicago wheat pit; bakers raise the loaf from five cents to ten and the poor line up for bread. Griffith cut back and forth between the farm, the feast and the breadline, a technique called parallel editing, so audiences saw both ends of the economy at once. The film drew on Frank Norris's stories and on a real scheme: months earlier Chicago financier James Patten had cornered wheat, sent bread prices up and made about $5 million, roughly $185 million today.