August, 1709
8/8: Portuguese Father Bartolomeu de Gusmao demonstrated a model hot air balloon to King John V.  He made the balloon (technically called envelope) out of paper, and inflated it by heating air from burning materials carried in a suspended container.  Today most envelopes are made out of reinforced nylon.  Learn about scientific experiments related to hot air balloons:  http://www.exploratorium.edu/ls/balloons/balloonscience.html

(source: The Learning Kingdom