Penny arcades became popular in the early 1900s. The first were tests of athletic strength, challenging patrons to “prove their manliness,” and marked the beginning of coin-operated vending machines (unless you count the Heron of Alexandria, a coin-operated holy water dispenser made in 215 BCE). For example, lifting machines required pulling on handles. Grip testers involved squeezing handles. Lung testers required blowing into a tube as long as possible. The Mills Submarine model featured four tiny deep sea divers on strings. As you blew, they were raised one-by-one. The Rubberneck model had a mannequin with a neck that stretched. The Hat Blower was just what it sounds like. Electricity testers dispensed electric shocks. To learn about Doctor Vibrator, a machine appealing to women, see BEHIND THE STORY.