Even a Londoner who has watched the birds in the aviary in Regent's Park knows that. But the bird is practising this art from the moment it leaves its nest. It has not only the perfect apparatus, but the perfect instinct to use it. A man off his feet has the poorest skill in balancing. Even the simple trick of the bicycle costs him some hours of labour. The instantaneous adjustments of the wings, the quick response to a passing breeze, the swift recovery of equilibrium, the giddy, eddying movements that require such absolute precision--all that he must learn, learn with infinite labour and infinite danger, if ever he is to conquer flying. The flying-machine that will start off some fine day, driven by neat "little levers," with a nice open deck like a liner, and all loaded up with bombshells and guns, is the easy dreaming of a literary man. In lives and in treasure the cost of the conquest of the empire of the air may even exceed all that has been spent in man's great conquest of the sea. Certainly it will be costlier than the greatest war that has ever devastated the world. No one knew these things better than these two practical men. And they knew they were in the front rank of the coming army. Yet there is hope even in a forlorn hope. Men are killed outright in the reserves sometimes, while others who have been left for dead in the thickest corner crawl out and survive. "If we miss these meadows"--said Woodhouse presently in his slow way. "My dear chap," said Monson, whose spirits had been rising fitfully during the last few days, "we mustn't miss these meadows. There's a quarter of a square mile for us to hit, fences removed, ditches levelled. We shall come down all right--rest assured. And if we don't"-- "Ah!" said Woodhouse. "If we don't!" Before the day of the start, the newspaper people got wind of the alterations at the northward end of the framework, and Monson was cheered by a decided change in the comments Romeike forwarded him. "He will be off some day," said the papers. "He will be off some day," said the South-Western season-ticket holders one to another; the seaside excursionists, the Saturday-to-Monday trippers from Sussex and Hampshire and Dorset and Devon, the eminent literary people from Hazlemere, all remarked eagerly one to another, "He will be off some day," as the familiar scaffolding came in sight. And actually, one bright morning, in full view of the ten-past-ten train from Basingstoke, Monson's flying-machine started on its journey.