“I must go, sir,” he said, relapsing into Esperanto.  “It is past nineteen o’clock.  Thank you so much.  Are you coming, father?”

Father Francis stood up also, in the dark grey suit permitted to priests, and took up his hat.

“Well, father,” said the old man again, “come again some day, if I haven’t been too discursive.  I suppose you have to write your letter yet?”

Percy nodded.

“I did half of it this morning,” he said, “but I felt I wanted another bird’s-eye view before I could understand properly:  I am so grateful to you for giving it me.  It is really a great labour, this daily letter to the Cardinal-Protector.  I am thinking of resigning if I am allowed.”

“My dear father, don’t do that.  If I may say so to your face, I think you have a very shrewd mind; and unless Rome has balanced information she can do nothing.  I don’t suppose your colleagues are as careful as yourself.”

Percy smiled, lifting his dark eyebrows deprecatingly.

“Come, father,” he said.

* * * * *

The two priests parted at the steps of the corridor, and Percy stood for a minute or two staring out at the familiar autumn scene, trying to understand what it all meant.  What he had heard downstairs seemed strangely to illuminate that vision of splendid prosperity that lay before him.

The air was as bright as day; artificial sunlight had carried all before it, and London now knew no difference between dark and light.  He stood in a kind of glazed cloister, heavily floored with a preparation of rubber on which footsteps made no sound.  Beneath him, at the foot of the stairs, poured an endless double line of persons severed by a partition, going to right and left, noiselessly, except for the murmur of Esperanto talking that sounded ceaselessly as they went.  Through the clear, hardened glass of the public passage showed a broad sleek black roadway, ribbed from side to side, and puckered in the centre, significantly empty, but even as he stood there a note sounded far away from Old Westminster, like the hum of a giant hive, rising as it came, and an instant later a transparent thing shot past, flashing from every angle, and the note died to a hum again and a silence as the great Government motor from the south whirled eastwards with the mails.  This was a privileged roadway; nothing but state-vehicles were allowed to use it, and those at a speed not exceeding one hundred miles an hour.

Other noises were subdued in this city of rubber; the passenger-circles were a hundred yards away, and the subterranean traffic lay too deep for anything but a vibration to make itself felt.  It was to remove this vibration, and silence the hum of the ordinary vehicles, that the Government experts had been working for the last twenty years.

Once again before he moved there came a long cry from overhead, startlingly beautiful and piercing, and, as he lifted his eyes from the glimpse of the steady river which alone had refused to be transformed, he saw high above him against the heavy illuminated clouds, a long slender object, glowing with soft light, slide northwards and vanish on outstretched wings.  That musical cry, he told himself, was the voice of one of the European line of volors announcing its arrival in the capital of Great Britain.