The Caquot is an elongated gas-bag, ninety-three feet long and twenty-eight feet in its widest diameter, made of rubberized cotton cloth and sharply streamlined. Hydrogen gas is the ascensive power used, lifting the cable, two men, basket, and all other equipment to a maximum altitude, in the best weather conditions, of over 5,000 feet. It has a balloonet, or air-chamber, within the main body of the gas-envelope, which as the balloon ascends fills automatically with air through a simple scoop placed under the nose of the balloon. The air and gas chambers are separated by a diaphragm of cloth. When the balloon is fully inflated this diaphragm rests on the underbody of the gas-envelope, there being no air in the balloonet. When the balloon descends, minus the several hundred feet of hydrogen which has escaped into the air, it would lose its shape and grow flabby, a condition of considerable potential danger, were it not for the balloonet, or air-chamber, coming into play. As the air is driven in through the scoop, precisely as an air-scoop fixed in the port-hole of an ocean liner brings air into a cabin, the diaphragm rises and takes up the lost bulk in the gas-envelope above. In other words, the escaping gas is replaced by air by means of what amounts to an elastic air-envelope below the gas-envelope. Is that quite clear? Three lobes of rubberized fabric give stability to the balloon. They are filled automatically by the wind, if it blows, and, expanding to their full capacity, act as rudders to hold the balloon steady. If there is no wind there is, of course, no need for the lobes and they hang loosely, like elephants’ ears, Caquots frequently being called “elephants” because of these drooping lobes. [Illustration: AN AMERICAN KITE BALLOON ABOUT TO ASCEND. The lobes of rubberized fabric give stability to the balloon. They are filled automatically by the wind, if it blows, and, expanding to their full capacity, act as rudders to hold the balloon steady.] [Illustration: PLANES IN BATTLE FORMATION. As accurately spaced as the pips on a card; as picturesque as a flock of geese southwardly bound.]