I have already mentioned the fact that thirty years ago the first rigid dirigible, the prototype of the modern Zeppelin, was built in Petrograd by the Russian, Captain Kostovitch. Its capacity was about 9,000 cubic metres of hydrogen and it was entirely constructed of a special light three-ply wood called "Arborit." Captain Kostovitch was obliged to devise machinery for the preparation of this wood, and the sheets, although they consisted often of twenty plies, could be made as thin as the thickness of a visiting card. Captain Kostovitch also invented a special method of his own for pressing the wood into any shape and using it for hollow spars and -girders, and his method was so successful that the wood became extremely strong and could hardly be affected even by acids. It was, of course, unaffected by water. The wood was used even for steam tubes, and it had the quality of lightness which is so essential in aviation. The Kostovitch dirigible was fitted with a ten-foot ladder perfectly rigid, capable of bearing a weight of half a ton, and yet only weighing six pounds! Seven separated balloons formed the body of the dirigible. The envelopes were made of a silk fabric manufactured and varnished according to a method of the inventor's which prevented a loss of gas of more than one per cent per day. A Zeppelin loses about two per cent. Thirty years have, passed since this dirigible was built. It can still be seen in Petrograd and it will be found that the silk remains as fresh and flexible and solid as it was on the day it was made.

Captain Kostovitch's persistence may be gathered from the fact that he had himself to design the looms for weaving the silk. The dirigible was equipped with two engines and possessed four propellers. The peculiar temper of the inventor and his love of secrecy prevented public acknowledgment and even the public knowledge of his achievement, and it has only recently become generally known that the Zeppelin was anticipated in Russia. The Kostovitch dirigible was fitted with a gondola with cabins from the centre of which a spiral staircase passed to a deck at the top. It will be remembered that only the very latest Zeppelins have this upper deck. The money necessary for its construction was provided by a number of Kostovitch's friends, among them M. A. Souvorin, the editor of the Novoie Vremya. In the files of the Russian technical magazines, several interesting illustrated descriptions of Kostovitch's invention may be found. It is rather curious that while Jules Verne was writing his famous romance of "The Albatross." He might by a simple journey to Petrograd have discovered his hero - the tall, dark captain with a long black beard - in the flesh, with a real airship of his own.

Years passed, and despite Kostovitch's achievement, Russia confined its interest to ordinary balloons and remained indifferent to the potentialities of the dirigible. Yet even before Kostovitch, Russians had thought out the possibility of constructing aircraft that could be steered, and a Russian Pole actually suggested to Napoleon that he should invade England by means of airships.

When at the beginning of what may be called the "Era of Air Conquest," both France and Germany began experiments with dirigibles, their efforts were watched with interest by the Russian authorities, who made many purchases in both countries. In 1910 the Russian army possessed twenty dirigibles of different types, eight of which were of considerable size. In that year Russia practically ceased to buy her dirigibles abroad and began to manufacture them herself. The War Office gave special encouragement to rubber and fabric manufacturers, and it is now generally admitted that the Russian envelopes are from the technical point of view superior to those manufactured in Germany and France. Russian dirigibles were built by Captain Shabsky, Colonel Golubeff, and Colonel Nemtchenko. Just before the war, a Shabsky airship was launched with a capacity of 20,000 cubic metres. The Zeppelin capacity is 22,000 cubic metres. It was fitted with four 170 h.p. Laviator engines. Four months earlier Colonel Golubeff's "Albatross" successfully took the air. Its capacity was 9,700 cubic metres and its engines had a total of 400 h.p. This airship beat the world's speed record for semi-rigid dirigibles. It is certain that both these dirigibles have performed valuable service during the war. So careful and experienced are the officers and crews of the Russian dirigibles that Russia has acquired a unique distinction among the countries that possess airship flotillas. Up to the outbreak of war there had not been one fatal accident resulting from their navigation, nor had one of the pilots been seriously injured.