Page 3 - Demo

in Coimbra. Later, he was selected as a member of the Academia Real de Hist%u00f3ria, and appointed chaplain to the Court. He continued to work on airship designs, but died in 1724 without really making any further progress.The Montgolfier brothers, Joseph and Etienne, were among 16 siblings of a French papermanufacturing family. While the two founded a paper-making vocational school, and invented a process to manufacture transparent paper, they are best remembered for their contributions to hot-air ballooning.While watching a fire one evening, Joseph noticed glowing embers lifting into the air. He guessed that smoke was buoyant, and later called it Montgolfier Gas, claiming it had the innate property of levity. Soon, he built a rectangular frame for a box (about 3%u2019 x 3%u2019 x 4%u2019) using thin wood strips, and covered all the sides, except the bottom, with a lightweight taffeta cloth. Then he crumpled some paper under the box and set it afire. The box quickly lifted into the air and hit the ceiling.Not long after his experiment, Joseph is said to have written to Etienne, %u201cGet in a supply of taffeta and of cordage quickly, and you will see one of the most astonishing sights in the world.%u201d Together, they built a larger fabric-covered box, and on December 14, 1782, sent it aloft. Surprised by the amount of its lifting force, they lost control of the device, and it floated more than a mile away before being destroyed after crashing into the ground.After more experimenting, on June 4, 1783 the brothers gave a public demonstration in the town of Annonay. This time, they used a much-improved paper-and-linen balloon that remained in the air for about ten minutes as a crowd of locals watched it climb to an altitude of 6,000 feet and travel for over a mile. Globe-shaped and thirtyfive-feet in diameter, this early Montgolfier