Here are some one liners...
The Gravity of an Apple Falling -- Newton's Apple falls and he realizes how gravity works. Now he has to prove it.
The Great Fire of London and St. Paul's Cathedral -- Flour dust explodes and the fire becomes so hot that people are cremated where they lay. St. Paul's Cathedral is rebuilt. I talk about the Blitz of WW 2 and a novel by Connie Willis.
The (False) Messiah Converts to Islam -- People are still talking about the false messiah who converts to Islam this year. I talk about how desperate people must be to latch on to someone like this.