Book 26, Question 91
Why did early parachutes swing wildly, and how did a vent hole help?
The first parachutes were big, closed umbrellas of cloth.
When André-Jacques Garnerin jumped from a balloon over Paris in 1797, his parachute swung back and forth so hard that he felt sick. Air kept spilling out from the edges first on one side, and then the other. A French astronomer, Joseph Lalande, suggested a hole at the top. Air escapes smoothly through it, so the parachute steadies.