I think it was these maps which first brought home to me distinctly how the spaces of the world had shrunk on the “time-scale” with the coming of the giant aeroplanes. The pace had been growing swifter and ever swifter since the middle of the nineteenth century. Up to that day, there had been little advance since the time of the earlier sailing-vessels. Then came the change from sail to steam; and the Atlantic crossing contracted in its duration. The great Trans-continental railways quickened transit once more; again there was a shrinkage in the time-scale. Vladivostok came within ten days of London; from Cairo to the Cape was only five days. But with the coming of the air-ways the acceleration was greater still; and we reckoned in hours the journeys which, in the nineteenth century days, had been calculated in weeks and even months. All the outposts of the world were drawing nearer together. It was not this shrinkage only which the air-maps suggested. In the early twentieth century the telegraphs and submarine cables had spread their network over the world, linking nation to nation and coast to coast; but their ramifications dwindled in perspective when compared with the complex network of the air-ways which now enmeshed the globe. London lay like a spider at the centre of the web of communications, the like of which the world had never seen before; and along each thread the aeroplanes were speeding to and from all the quarters of the earth. Rapid communication we had had since the days of the extension of the telegraph; but it had been limited to the transmission of thoughts and of news. The coming of the aeroplanes had changed all that. These tracks on the air-maps were not mere wires thrilling with the quiverings of the electric current. Along them material things were passing continually; a constant interchange of passengers and goods was taking place hourly over the multitudinous routes. For good or ill, humanity was becoming linked together until it formed a single unit. It is curious that all the prophetic writers of the early twentieth century concentrated their attention almost exclusively upon the racial and social reactions which might be expected to follow from this knitting of the world into a connected whole and the resultant increase of traffic between the nations over the now contracted world-spaces. They had seen the interminglings of races which began in the steamship days; and they deduced that the process would be intensified in the new era of air-transit; so that, in the end of their dreams, they saw the possibility of a World Federation stretching its rule over the whole globe and bringing with it the end of wars. None of them, strangely enough, had foreseen the real effects which this intercommunication was to bring forth.