He acknowledged that there was something peculiar in Limanora that made this adaptation easier; a magnetism seemed to come from the earth that made the force of gravitation less; there was also something more exhilarating in the atmosphere and climate that differentiated it from all other lands. This explained why I had so rapidly acquired the tripping, noiseless gait I had so admired when first I saw Noola. There had been a time in the history of the earth when the human body was so light and agile in proportion to its size that a few coincidences in nature, as, for example, the increase of swift land and tree enemies, would have made it ultimately winged. That was the geological epoch, when, after a period of great contraction and increase of density (the period of the huge saurians and other monsters of the prime), the orb had, through volcanic explosions within it and the impact of myriads of aërolites on its crust, expanded its texture and partially volatilised its internal elements. Since then it has been cooling down within, and thus growing less in size, though losing none of its mass; this can be seen in the twistings and foldings of the rocks and the enormous wrinkles on its surface. The result has been that animals, and men with them, have been growing heavier for their size. The possibility of man becoming a flying race has passed away. Land and sea animals have no longer the chance of developing into birds of the air; and even some of the tribes of winged things have almost surrendered their prerogative of flight; nothing but embryo and unused wings remain to them. It is only in exceptional spots like Limanora, where the magnetic conditions and the spongy nature of the interior of the earth lessen the force of gravitation, that men could ever acquire the power of artificial flight with any ease. By dint of the application of enormous force, and of inventive mechanical power, men in other lands may master the art of aërial voyaging; but it will never become an accomplishment of the individual; there will be too much strain and stress for it ever to grow a pleasant mode of travel. Thus Oolmo flashed light upon the past and the future as we traversed the groves of Fialume. We grew familiar with the great forces of the universe, and their bearing upon the problems of mankind, and gained the true perspective of existence. I felt that Europe was but standing still, reform herself and advance in science and art and civilisation as quickly as she might. European man himself was not progressing, but only the external results of his individual efforts. It would take ten thousand years for the huge nations of Europe to make the step upwards that these islanders made in a day. Material progress meant nothing to the Limanorans unless it meant also the progress of the men themselves in capacity, in power of attaining higher and higher goals.