Balloon
a bag filled with hydrogen, coal gas, hot air, or some other gas lighter than the atmosphere. When released, the downward pressure of the atmosphere forces the balloon upward until it reaches a position in the atmosphere where its weight is equal to that of the air displaced. Balloon ascensions are accomplished in a light car or cage attached to a large balloon. Those who make the attempt are called aeronauts, or air navigators. A navigator carries usually a supply of ballast, or sand in bags, which he may throw out if he desires his car to rise higher. The balloon is furnished with a valve controlled by a cord so that the navigator may allow gas to escape when he wishes to come down. Balloon navigation is attended with great risks. Sometimes a balloon is caught in an upper current of air, and carried away off to the ocean, where it is never heard of again. Not infrequently some accident causes the entire contrivance to drop to the ground, killing the occupants of the cage.
The construction of the first balloon is credited to Stephen and Joseph Montgolfier, sons of a paper maker of Annonay, France. They experimented at first with paper bags filled with smoke. Then they constructed a linen bag about thirty feet in diameter, and filled it with hot air by means of a straw fire. This balloon rose June 5, 1783, to a height of about a mile and one-half to the great astonishment of the villagers. In August of the same year M. Charles of Paris constructed a large silk balloon, and, after four days of work with sulphuric acid and iron filings, succeeded in filling it with hydrogen gas. He allowed it to rise from the Champ de Mars in Paris. It rose to a height of about 3,000 feet, and remained in full view of an immense crowd of people for about three quarters of an hour. It then drifted away and fell about fifteen miles off in the field of some peasants, who were terrified beyond measure and attacked it and tore it to pieces under the impression that it was a dangerous monster of some sort. In November of the same year two Frenchmen attached a car to a balloon. They rose about 500 feet, remained twenty-five minutes in the air, traveling a horizontal distance of five miles.
From this time on one experiment succeeded another. A high ascension was made September 5, 1862, by Messrs. Glaisher and Coxwell. They reached a height of 29,000 feet, or about five and one-half miles. At that height they recorded a temperature of --2 deg. F., and a barometric pressure of 11.28 inches. Professor Berson of Berlin ascended in 1894 to a height of 28,750 feet. His record shows a temperature of --54 deg. F. and a barometric pressure of 9.12 inches. It must be said, however, that it is very difficult for a navigator to take correct observations, owing not only to the extreme cold, but to the paralysis which results from want of air.
During the Franco-Prussian War, 1871, the besieged inhabitants of Paris, the scientific center of ballooning, maintained communication with the outer world by means of balloons. Over sixty were sent out. Since that date, regular balloon corps have been maintained in connection with armies, especially those of France and Germany. Observation balloons were used very successfully by the Japanese during their war with Russia. A recent device is the addition of a camera with which to make photographic observations. At a height of 3,000 feet a fleet thirty miles away may be photographed. The gas bags of war balloons consist of two thicknesses of raw silk. Between these is a coating of liquid rubber. Bullet holes close at once, allowing little gas to escape.
A number of long journeys are on record. Balloons sent up at the Paris Exposition in 1900 made remarkable journeys to Sweden, Germany, and Poland. One traveled 1,193 miles in 36 hours and 45 minutes. The greatest height attained by any of these balloons was 21,582 feet. Two Frenchmen journeyed by balloon from Crystal Palace, London, to St. Denis, a suburb of Paris, a distance of 250 miles, in 6 1/2 hours. Empty balloons have been sent up beyond the limits of human life. In 1893 a balloon with a self-registering barometer was sent up at Paris. If the instrument record is correct, the balloon rose nearly ten miles. A balloon sent up at Berlin reached an altitude of eleven and one-half miles. A self-registering barometer recorded 75 deg. below zero.
Balloons are now provided with steering apparatus and even propellers. Benbow's airship exhibited at the St. Louis Exposition attracted attention. It had an aluminum frame, and an oval gas bag 75 feet long and 20 feet in diameter. The bag contained 16,000 cubic feet of gas. A gasoline engine drove a propeller with collapsing paddles, built somewhat after the principle of a duck's foot.
In 1908 Count Zeppelin of Germany constructed a dirigible balloon 420 feet long and 40 feet in diameter. July 1 he ascended and remained in the air twelve hours, keeping his ship under perfect control, and sweeping about in graceful curves. He traveled at an average speed of thirty-four miles an hour. A month later his ship was consumed by fire while at anchor. The Germans promptly subscribed $1,000,000 with which to build a new one. In 1909 the plucky Count was in the air again with a new and still better airship. March 22 the huge dirigible ascended from its quarters at Lake Constance, bearing Count Zeppelin with ten aeronauts of the German army and fifteen soldiers. A great throng witnessed the ascent. The airship rose as majestically as an eagle. Its flight covered 150 miles, and the dirigible was in the air four hours.
The greatest balloon race ever held in the United States started at St. Louis October 21, 1907. Nine balloons entered the race. Three of them represented German owners; two came from France; one from England; and three belonged in the United States. The great balloons, released amid the waving of flags and playing of national airs, rose into an upper current of air and disappeared eastward. One American balloon landed near Hamilton on the shore of Lake Erie, covering 650 miles in 26 hours. The English balloon abandoned the contest in Ohio. Two landed in Virginia. Two fell in Maryland. The Pommern, a huge German balloon, arrived at Asbury Park, New Jersey, and, not daring to venture out over the ocean, the owner came down 40 hours and 873.4 miles from St. Louis, and won the distance cup. The French balloon L'Isle de France descended at Herbertsville, New Jersey, five miles nearer St. Louis, but 43 hours and 59 minutes in the air, and won the world's record for duration of flight. A world's distance record of 1,193 miles was made in 1900.
See Airship; Gas; Air; Altitude; Andree; Zeppelin