But these were by no means the only inventions of the war. Great Britain showed wonderful ingenuity and resourcefulness in many directions; France did marvels with the airplane and showed great cleverness in her development of the tank and there was a host of minor inventions to her credit; while Italy showed marked skill in the creation of large airplanes and small seacraft. The Central Powers, on the other hand, were less originative but showed marked resourcefulness in developing the inventions of others. Forts were made valueless by the large portable Austrian guns. The long range gun that shelled Paris was a sensational achievement, but it cannot be called a great invention because it was of little military value. The great German Zeppelins were far from a success because they depended for their buoyancy on a highly inflammable gas. It is interesting to note that while the Germans were acknowledging the failure of their dirigibles the British were launching an airship program, and here in America we had found an economical way of producing a non-inflammable balloon gas which promises a great future for aërial navigation. The most important German contribution to the war--it cannot be classed as an invention--was poison gas, and it was not long ere they regretted this infraction of the rules of civilized warfare adopted at the Hague Conference; for the Allies soon gave them a big dose of their own medicine and before the war was over, fairly deluged them with lethal gases of every variety. Many inventions of our own and of our allies were not fully developed when the war ended, and there were some which, although primarily intended for purposes of war, will be most serviceable in time of peace. For this war was not one of mere destruction. It set men to thinking as they had never thought before. It intensified their inventive faculties, and as a result, the world is richer in many ways. Lessons of thrift and economy have been taught us. Manufacturers have learned the value of standardization. The business man has gained an appreciation of scientific research. The whole story is too big to be contained within the covers of a single book, but I have selected the more important and interesting inventions and have endeavored to describe them in simple language for the benefit of the reader who is not technically trained. A. RUSSELL BOND New York, May, 1919 CONTENTS CHAPTER PAGE I THE WAR IN AND UNDER THE GROUND 3 II HAND-GRENADES AND TRENCH MORTARS 20 III GUNS THAT FIRE THEMSELVES 41 IV GUNS AND SUPER-GUNS 62 V THE BATTLE OF THE CHEMISTS 85 VI TANKS 107 VII THE WAR IN THE AIR 123 VIII SHIPS THAT SAIL THE SKIES 148