The epochs of invention go hand in hand with the history of civilization, for it has been largely through invention that man has been able to progress to better methods of living. In the olden days, when there were few towns and every one lived in a castle, or on the land owned by the lord of the castle, war was the chief occupation, and the little communities made practically everything they used by hand. When they went abroad they either walked or rode horses, or went in clumsy ships. Pretty soon men began to invent better ways of doing things; one a better way of making shoes, another a better way of making armour, and the people for miles around would take to going to these men for their shoes and armour. Towns sprang up around these expert workmen, and more inventions came, bringing more industries to the towns. Inventions made industry bigger, and war more disastrous because of the improvement invention made in weapons. Then came inventions that changed the manner of living for all men--the machines for making cloth, which did away with the spinning-wheels of our great-grandmothers, and created the great industry of the cotton and woollen mills; the inventions for making steel that brought about the great steel mills, and enabled the armies of the world to use the great guns we know to-day, and the battleships to carry such heavy armour plate; the steam locomotive that enabled man to travel swiftly from one city to another; the steamship that brought all the nations close together; the telegraph, cable, telephone, and wireless, that made communication over any distance easy; the submarine that made war still more dangerous; and finally the aeroplane that makes a highway of the air in which our earth revolves. But even from the time of the ancient Greeks and Romans man had tried to fly. Every nation had its list of martyrs who gave their lives to the cause of aviation. In modern times, too, many attempts had been made to discover the secret of flight. Otto Lilienthal, a German, called the "Flying Man," had made important discoveries about air currents while gliding through the air from hills and walls by means of contrivances like wings fitted to his person. Others had made fairly successful gliders, and Prof. Samuel Pierepont Langley of the Smithsonian Institution in Washington actually had made a model aeroplane that flew for a short distance. Also, Clement Ader, a Frenchman, had sailed a short way in a power flier, and Sir Hiram Maxim, the English inventor, had built a gigantic steam-driven aeroplane that gave some evidences of being able to fly. But these men were laughed at as cranks, while the Wrights kept their secret until they were sure of the success of their biplane. However, the question as to who first rode in a power-driven flier under the control of the operator still is the subject of a world-wide controversy.