The moment I reached the office I rang up the Record, our evening sheet. But their reporters were still out, and nobody could yet tell me anything about the accident I didn't already know. Willett, my young colleague on the Circus, did not propose to give the story exceptional treatment.

"If the thing caught fire in the air we'll let it alone," he said. "Fire's too much of a bugbear. We want the joy-riding idiot and the lunatic who stunts over towns. I'm for letting it alone, but we'll wait and see what the others do."

He was quite right. On its merits as Publicity it looked as if we should hear little more of the Case. I settled down to my work.

I had not actually expected that Hubbard would ring me up, but I was not greatly surprised when, at about four o'clock, he did so. He wanted to know whether I could go round to the Admiralty at once. That we must have a talk at the earliest possible moment was a foregone conclusion. I therefore replied that I would be on my way in ten minutes, and, hastily swallowing the cup of tea that had been placed on my desk and telling Willett to carry on, I took up my hat and stick, sought the lift, threaded my way through the Record's carts and bicycles and boarded a passing motor-bus in Fleet Street.

I had no very clear notion of the nature of the job that kept Hubbard in town that spring, and that had caused him to envy Esdaile his luck in being able to get away into the country. Indeed, I can tell you very little about the organization of that mysterious Service that moves, familiar yet isolated, in our midst. I understood that originally he had been a torpedo man, but had later been drafted into the Inventions branch. It is quite possible that the scope of his work had been expressly left rather ill-defined. So many amazing extemporizations had to be hurriedly made and applied.

Still, these war-improvisations have to be overhauled afterwards, so that it may be seen which disappear with the emergency, and which are to be permanently incorporated in the strategy of the future; and I knew that one at any rate of Hubbard's tasks was to explain to a certain Parliamentary Committee a number of technical and basic facts that have a way of not varying very much however the political situation may change.

I found him alone in his room on the third floor. The screen just within the door was so disposed that, in the spot to which your eyes naturally turned on entering, the officer you had come to see was not. They are old in cunning in the Senior Service, and I had never seen Hubbard at work before. His voice came to me from quite a different part of the room, and I had the feeling that if I had been a stranger there would have been a moment in which I should have been pretty thoroughly looked up and down.

"Come in and take a pew," he said. "Hope I haven't fetched you away from anything important. But I couldn't stop to talk this morning. I only got rid of my By-election Blighters half an hour ago. Well——"

And, as I sat down in the chair at the end of his desk, he plunged straight into the matter by asking me how long I had known Esdaile.

Now how long you have known a man, in the sense of how well you know him, is not always simply a matter of time. I have told you how humdrum my own War services were. They had not included those incredible moments of intensified action that may more truly reveal a man to you than years of desultory familiarity. It was plainly something of this kind that Hubbard had in his mind now. He frowned as he trifled with a paper-weight.

"No, it's absolutely unaccountable," he broke out suddenly, putting the paper-weight down with a slap. "He's not that kind of man. It simply doesn't fit in."

"His behavior this morning, you mean?"

"Yes. It was another man altogether. Why, before I knew Esdaile well I remember I bet him a supper that he'd drop his palette on the quarter-deck when the first shell came over. Well, it came, and half the bridge was wrecked, and he never turned a hair. Just carried on with that sketch of Hopkins at the range-finder. Absolutely undefeated sportsman. So why should he behave as he did this morning?"

Hereupon—though not as throwing very much light on the question after all—I told Hubbard of my own surmise with regard to Rooke. He looked rather quickly up.

"What, little Queerfellow? He's—er—all right, isn't he? What about him? Tell me about him."

This too I told him as well as I was able. And I may say that I noted with pleasure, as perhaps the real beginning of a valued friendship, that there did not seem to be any question in Hubbard's mind as to what kind of man I was myself. He was quite content to accept my summing-up of Monty.

"So it's between 'em, you think, whatever it is?"

"Or else I give it up," I replied.

"I wonder if you're right," he mused.... "But then," he added suddenly, "what about all that time he spent in the cellar?"

From that point our conversation took for a time a curious little turn.

For Hubbard, while seeming to have no explanation that as a sensible man he must not reject as fantastic, seemed nevertheless to be reluctant to let something go. He seemed to hint and to dismiss and then to hint again, to come to the brink of saying something and then to leave it unsaid after all. And again I had the feeling that though he had known Philip Esdaile for only two years as against my twenty, in some things he might be the familiar and I the outsider.

Then again he seemed to decide to take a risk. He spoke to the paper-weight in his palm.

"You don't happen to know anything about these new sound-appliances, do you?" he asked.

"No. Which are they?"

"Oh, there are a lot of 'em," he answered again, half evasively. "There's sound-ranging, of course. Then there's the hydrophone. And as a matter of fact the best brains in the world to-day are trying to cut-out sound—aeroplane propellers and so on.... What I mean is Esdaile's not hearing anything. I suppose it's just possible that he didn't. All a matter of where the sound-wave hits. You remember the broken windows in the Strand when Fritz used to come over and drop his eggs? First a broken one, then two or three whole ones, then broken ones again, all along the street? Well, this might have been one of those dumb intervals. Otherwise he must have heard. And I should have thought he'd have felt the vibration too."

"He's admitted he thought he heard something."

"Pooh, there was no mistaking it. If he didn't recognize it we can take it he didn't hear it. If we believe him, of course."

"Don't you believe him?"

"Yes," Hubbard answered without a moment's hesitation.

"Then——?"

"Oh, I suppose it means I'm on the wrong track," Hubbard replied.

Naturally any track of that nature was totally unexplored by me; but I was far from dismissing it on that account. Here again my ignorance of modern War came in to humble me. For what is the good of saying things are fantastic and far-fetched—sound-ranging and the selenium cell and what not—when for a number of years the food we have eaten and the clothes we have worn and the roofs over our heads have depended on just such fantasies? Not for nothing were those clusters of listening cones at Hyde Park Corner and on Parliament Hill, not for nothing those wireless masts over our heads at that very moment. Their operation might be unfamiliar to me, but these things were the daily business of Commander Hubbard, R.N. He turned as naturally to them as I myself turn to those equally mysterious things, a man's motives and the operative emotions of his heart.

"For all that," said Hubbard abruptly, "I should like to have a good look at that cellar of his."

I was silent. I didn't know whether his wish to see the cellar included sound-experiments on the roof also.

"More than that," he continued slowly, "—by the way, did Mrs. Esdaile and the children get away?"

That I did not know.

"Well, what about going round this evening to see?"

"The chances are that they did if I know Philip."

"I don't mean that. I mean what about going round to see that cellar," Hubbard replied.

I didn't say so, but I had a sudden wonder, quite new and born all at once of I don't know what, whether Esdaile might want us to see his cellar.