A knightly stroll, with treadmill and respiration mask
Medieval knighthood was physically grueling work: Jousting with massive lances. Charging into battle. Jogging on a treadmill in a full suit of armor. You know how it is.
It’s no surprise that beneath their shining armor, knights shimmered with sweat. Running around in up to 110 pounds of armor, or even advancing at a stately walk, would take a whole lot of effort. But, a team of scientists wondered, just how exhausting was it?
Here’s the situation: You spot Roman attack ships headed for your shores. Do you order your troops to ready the cannons? Or–in an ancient MacGyver move–do you use a parabolic mirror, focusing the sun’s rays to set the ships on fire? Though the latter is clearly more suave, recent research has shown that the 212 B.C. legend about Archimedes’ mirror defense is unlikely: He probably pulled out the big guns instead.
Cesar Rossi, a mechanical engineer at the University of Naples in Italy, figured out the numbers. A steam cannon–like the ones Leonardo da Vinci drew in the 1400s–could use less than a tenth of a cup of water to fire a hollow clay ball, at 134 miles per hour, to hit a target 492 feet away. For comparison, an 1854 American Civil War Howitzer cannon could fire a ball about ten times farther–a little less than a mile.