Rob and Chris learn about the Industrial Age. Trains are still a thing and they're still being talked about. Alexander Graham Bell invents the telephone and immediately turns into a pompous prick. Although he was described as "a dull boy," Thomas Edison goes on to light a whopping 40 light bulbs at once! Crude oil was first used as medicine until people realized it was disgusting and made them feel worse. Before the telephone people were into telegraph sex, though it was a bit awkward.
TLDR: Inventions that no longer seem that great!
