A French "Sausage".

Though Count von Zeppelin had begun his experiments in 1873 it was not until 1890 that he actually began the construction of his first airship. The intervening years had been spent in constructing and testing models, in abstruse calculations of the resistance of the air, the lifting power of hydrogen, the comparative rigidity and weight of different woods and various metals, the power and weight of the different makes of motors. In these studies he spent both his time and his money lavishly, with the result that when he had built a model on the lines of which he was willing to risk the construction of an airship of operative size, his private fortune was gone. It is the common lot of inventors. For a time the Count suffered all the mortification and ignominy which the beggar, even in a most worthy cause, must always experience. Hat in hand he approached every possible patron with his story of certain success if only supplied with funds with which to complete his ship. A stock company with a capital of $225,000 of which he contributed one half, soon found its resources exhausted and retired from the speculation. Appeals to the Emperor met with only cold indifference. An American millionaire newspaper owner, resident in Europe, sent contemptuous word by his secretary that he "had no time to bother with crazy inventors." That was indeed the attitude of the business classes at the moment when the inventors of dirigibles were on the very point of conquering the obstacles in the way of making the navigation of air a practical art. A governmental commission at Berlin rejected with contempt the plans which Zeppelin presented in his appeal for support. Members of that commission were forced to an about-face later and became some of the inventor's sturdiest champions. But in his darkest hour the government failed him, and the one friendly hand stretched out in aid was that of the German Engineers' Society which, somewhat doubtfully, advanced some funds to keep the work in operation.

© U. & U.

A British "Blimp".

With this the construction of the first Zeppelin craft was begun. Though there had been built up to the opening of the war twenty-five "Zeps"—nobody knows how many since—the fundamental type was not materially altered in the later ones, and a description of the first will stand for all. In connection with this description may be noted the criticisms of experts some of which proved only too well founded.

The first Zeppelin was polygonal, 450 feet long, 78 broad, and 66 feet high. This colossal bulk, equivalent to that of a 7500-ton ship necessary to supply lifting power for the metallic frame, naturally made her unwieldy to handle, unsafe to leave at rest, outside of a sheltering shed, and a particularly attractive target for artillery in time of war. Actual action indeed proved that to be safe from the shells of anti-aircraft guns, the Zeppelins were forced to fly so high that their own bombs could not be dropped with any degree of accuracy upon a desired target.

The balloon's frame is made of aluminum, the lightest of metals, but not the least costly. A curious disadvantage of this construction was made apparent in the accident which destroyed Zeppelin IV. That was the first of the airships to be equipped with a full wireless outfit which was used freely on its flight. It appeared that the aluminum frame absorbed much of the electricity generated for the purpose of the wireless. The effect of this was two-fold. It limited the radius of operation of the wireless to 150 miles or less, and it made the metal frame a perilous storehouse of electricity. When Zeppelin IV. met with a disaster by a storm which dragged it from its moorings, the stored electricity in her frame was suddenly released by contact with the trees and set fire to the envelope, utterly destroying the ship.

The balloon frame was divided into seventeen compartments, each of which held a ballonet filled with hydrogen gas. The purpose of this was similar to the practice of dividing a ship's hulls into compartments. If one or more of the ballonets, for any reason, were injured the remainder would keep the ship afloat. The space between the ballonets and the outer skin was pumped full of air to keep the latter taut and rigid. Moreover it helped to prevent the radiation of heat to the gas bags from the outer envelope whose huge expanse, presented to the sun, absorbed an immense amount of heat rays.