Balloons Carry Humans

Overview

With the balloon, the Montgolfier brothers brought flight to humans, initiating an era of fun and experimentation. Within a dozen years, there were scientific expeditions, competitions, recreational excursions, and military applications—a pattern that would be repeated when powered flight arrived a bit over a century later. Scientists took advantage of the new device to measure temperatures, wind patterns, and atmospheric composition. The military first used balloons to spot artillery and terrify the enemy. From the first, balloons attracted hundreds of thousands of spectators, and today, recreation is the main reason for ballooning, which continues to fascinate the public.

Background

Archimedes (c. 287-212 b.c.) established the principle of buoyancy in the third century b.c., but it was not until Joseph and Étienne Mont-golfier began their experiments with balloons that the principle was put to use for flight. Francis Bacon (1561-1626) is sometimes given credit for the concept of the balloon, having written in 1250 about creating a flying machine by filling a hollow globe of copper with "ethereal air" or "liquid fire." In 1670 an Italian priest saw the air pump as a possible means for building Bacon's flying machine. His vehicle was based on scientific principles and looked good on paper. Unfortunately, when the copper was made thin enough to reduce its weight, the force of the vacuum collapsed the ball. A Brazilian priest had more success. In 1709 he created a small, working model of a balloon for the king of Portugal. He used hot air, just as the Montgolfier brothers would. When he lit the fire, the model drifted across the room and set the curtains on fire but failed to ignite anyone's imagination.

Independently of those predecessors, Joseph-Michel Montgolfier (1740-1810) conceived of the balloon in 1782 when he supposedly noticed the billowing of a shirt next to a drying fire. (A less romantic story holds that he was inspired by Joseph Priestley's experiments with gases.) Borrowing some rags from his landlady, he made a small model that took off into the air. He knew immediately that he had discovered something important. He sent for his brother Jacques-Etienne (1745-1799), and the two were soon experimenting by sending paper bags up a flue. On April 4, 1783, they held their first public demonstration. The bag was made of cloth and paper. (The Montgolfier family was in the paper business.) It was coated with alum to reduce its flammability—a good idea since the bag was filled with hot air created by burning straw. The contraption was held together with over 2,000 buttons. To the amazement and delight of the crowd, the balloon rose to a height of 2,000 feet (600 m) and traveled almost a mile (1.6 km).

The first balloon passengers were a sheep, a duck, and a rooster. The balloon that was used, however, was not a toy; it was 110 feet (34 m) in circumference and weighed 500 pounds (200 kg). The Montgolfiers set the balloon aloft in Versailles on September 19, 1783, before a crowd of 130,000. The animals traveled and landed safely. The next step was a tethered flight. Jean François Pilâtre de Rozier, a professor of physics, was the first human to fly, reaching a height of 85 ft (26 m) over Paris. It was now time for the first free flight. The king offered to provide a condemned prisoner as the test pilot, but Rozier wanted the honor for himself. He and François Laurent, an aristocrat and an infantry officer, took off on November 21, 1783. Theirs was not an uneventful journey. While in transit, the silk and paper balloon first sank to rooftop levels and then started to burn. The two men used wet sponges to keep their vehicle from burning up and landed safely after traveling about 7 miles (11 km). Local villagers were concerned about the strange device, but their worries disappeared when they were offered champagne.

Within weeks, Jacques Charles (1746-1823) and Nicolas Robert were aloft in a hydrogen-filled balloon. Theirs was a much longer journey, rising to 3,000 feet (900 m) and going 16 miles (26 km). Hydrogen, discovered in 1766 by Henry Cavendish (1731-1810), is significantly lighter than nitrogen, the main component of air. Apparently, Charles assumed the Mont-golfiers were using hydrogen and was unaware of how innovative he was. When the balloon landed near a farming village, the villagers mistook it for a dragon and attacked it. After the balloon was totally demolished, they even had the local priest exorcise the demon. To protect future balloons, the king issued a royal proclamation against attacking balloons. Charles's new balloon was financed by charging some of the 400,000 spectators of the next flight (including Benjamin Franklin) a crown apiece.

Impact

The Montgolfiers continued their careers as inventors, developing the hydraulic ram (which uses the energy of flowing water to force a small portion of the water upward), the calorimeter, and a method for producing vellum, a fine-quality paper used for formal documents. Charles also continued to work as an inventor, improving many instruments and developing the hydrometer and the reflecting goniometer (used to measure angles). He is also famous for Charles's Law (different gases all expand the same amount with a given increase in temperature).

The dramatic and successful demonstrations by both the Montgolfiers and Charles created a ballooning craze across Europe. Within a year, there were flights in England, Scotland, and Italy. The balloonists worked to best each other, perfecting control of the craft, rising to higher and higher levels. Attempts were made to add propulsion, using oars, wings, and propellers. As early as 1784, a French general designed the first dirigible, which featured hand-cranked propellers and a cigar shape, but the first practical powered balloon was not invented until 1852, when Henri Giffard (1825-1882) flew a steam-powered dirigible.

The first trip across the English Channel by balloon was also the first instance of international airmail. Jean Pierre Blanchard (1753-1809), a French aeronaut, and John Jeffries, an American physician, took off from England in 1785 in a balloon laden with food, flags, and mementos. Unfortunately, their balloon began to sink as they traveled over colder water. They began to jettison everything to gain lift, including most of their clothing. When they landed in France, they had little more left than a bottle of brandy and a packet of letters. Blanchard continued as a pioneer. He invented the parachute and tested it by dropping a dog in a basket from a balloon in 1785. In 1793 he launched the first balloon in North America, from Washington Prison Yard in Philadelphia. But it was not until 1978 that the first transatlantic balloon trip was completed. The Double Eagle II was piloted by Americans Troy Bradley and Richard Abruzzo and went from Maine to France. In 1999 the Breitling Orbiter 3 became the first balloon to travel nonstop around the world. It headed east from Switzerland and ended its journey in Egypt. It was piloted by Swiss psychiatrist Bertrand Piccard (1958- ) and British pilot Brian Jones (1947- ).

The French promoted the scientific use of balloons. In 1784 samples of air taken at high altitudes were brought back to Earth to be studied. Scientists also carried instruments up in balloons to measure temperature, pressure, and humidity. In 1804 Jean Baptiste Biot (1774-1862) and Joseph Louis Gay-Lussac (1778-1850) went up in a balloon left over from Napoleon's Egyptian campaign. They brought along small animals and scientific instruments and proved that Earth's magnetism was undiminished at altitudes up to 3 miles (5 km). Gay-Lussac later went up to a height of 4 miles (6 km).

More recently, balloons have been used to investigate radio rays and to establish the existence of cosmic rays. Balloons are still launched to determine the speed and direction of winds (a practice that gave rise to the phrase "send up a trial balloon"). Currently, 1,000 readings of wind, temperature, humidity, and pressure in the upper atmosphere are taken each day by weather balloons.

It did not take long for the military potential of balloons to be realized. As early as 1793, Jean Pierre Coutelle used a balloon at the Battle of Maubeuge to spot artillery and demoralize the enemy. Napoleon used balloons and, during the Franco-Prussian War (1870-1871), balloons were dramatically used to carry 164 people and 20,000 lbs (9,000 kg) of mail out of the besieged city of Paris. Both sides in the American Civil war used them for reconnaissance. A Union volunteer, Count Ferdinand von Zeppelin (1838-1917), became fascinated with balloons and, beginning in 1891, dedicated his life to making practical airships. By adding propulsion and a lightweight frame, he invented the aircraft that bears his name. Zeppelins first flew in 1900. By 1910 they were providing regular flights between German cities and, later, they flew scheduled, commercial transatlantic flights, cruising at 68 miles (110 km) per hr. During Word War I, Zeppelins were used as bombers. At the same time, the British used traditional balloons for aerial photography. The military continued to find applications for balloons as late as World War II. Tethered by chains, they formed a part of antiaircraft defense, making attacks more difficult by forcing planes to fly above them. The British also used them for submarine detection and, after the war, balloons were used for defense as flying radar stations. Ultimately, the vulnerability of balloons to weather and enemy fire made their use in warfare obsolete, although in 1979, during the Cold War, a balloon was used by two families to fly from East to West Germany. Afterward, the sale of lightweight fabric was restricted in East Germany.

Today, while advertisement-covered, helium-filled blimps are the most visible application of balloons, recreational hot-air balloons actually dominate the lighter-than-air world. Through most of the early part of the twentieth century, ballooning was a rich person's sport, like yachting. The Gordon Bennett Balloon Trophy Races helped popularize the sport. In Europe, this tradition has continued but, in America, the invention of an inexpensive, highly controllable hotair balloon popularized the sport. In the 1950s, Ed Yost, an employee at General Mills, put his expertise in cellophane packaging to work for the U.S. military. He helped build giant polyethylene balloons for stratospheric research. Inspired by the new materials, he pursued the opportunity to design simple, relatively safe, and less-expensive balloons. Made of polyurethanecoated nylon fabric and powered by a propane burner, the Raven became the first modern hotair balloon when it took to the skies in 1960.

PETER J. ANDREWS