But the command pa.s.sed unheeded; the latch was not raised, and only the slightest tap was heard.

With a bound he reached forward and pulled the door open. Then a great silence fell upon him and a rigidity as of the grave seized and stiffened his powerful frame.

The man confronting him from the darkness was Sweet.w.a.ter.

x.x.xVI. THE MAN WITHIN AND THE MAN WITHOUT

An instant of silence, during which the two men eyed each other; then, Sweet.w.a.ter, with an ironical smile directed towards the pistol lightly remarked:

"Mr. Challoner and other men at the hotel are acquainted with my purpose and await my return. I have come--" here he cast a glowing look at the huge curtain cutting off the greater portion of the illy-lit interior--"to offer you my services, Mr. Brotherson. I have no other motive for this intrusion than to be of use. I am deeply interested in your invention, to the development of which I have already lent some aid, and can bring to the test you propose a sympathetic help which you could hardly find in any other person living."

The silence which settled down at the completion of these words had a weight which made that of the previous moment seem light and all athrob with sound. The man within had not yet caught his breath; the man without held his, in an anxiety which had little to do with the direction of the weapon, into which he looked. Then an owl hooted far away in the forest, and Orlando, slowly lowering his arm, asked in an oddly constrained tone:

"How long have you been in town?"

The answer cut clean through any lingering hope he may have had.

"Ever since the day your brother was told the story of his great misfortune."

"Ah! still at your old tricks! I thought you had quit that business as unprofitable."

"I don't know. I never expect quick returns. He who holds on for a rise sometimes reaps unlooked-for profits."

The arm and fist of Orlando Brotherson ached to hurl this fellow back into the heart of the midnight woods.

But they remained quiescent and he spoke instead. "I have buried the business. You will never resuscitate it through me."

Sweet.w.a.ter smiled. There was no mirth in his smile though there was lightness in his tone as said:

"Then let us go back to the matter in hand. You need a helper; where are you going to find one if you don't take me?"

A growl from Brotherson's set lips. Never had he looked more dangerous than in the one burning instant following this daring repet.i.tion of the detective's outrageous request. But as he noted how slight was the figure opposing him from the other side of the threshold, he was swayed by his natural admiration of pluck in the physically weak, and lost his threatening att.i.tude, only to a.s.sume one which Sweet.w.a.ter secretly found it even harder to meet.

"You are a fool," was the stinging remark he heard flung at him. "Do you want to play the police-officer here and arrest me in mid air?"

"Mr. Brotherson, you understand me as little as I am supposed to understand you. Humble as my place is in society and, I may add, in the Department whose interests I serve, there are in me two men. One you know pa.s.sably well--the detective whose methods, only indifferently clever show that he has very much to learn. Of the other--the workman acquainted with hammer and saw, but with some knowledge too of higher mathematics and the principles upon which great mechanical inventions depend, you know little, and must imagine much. I was playing the gawky when I helped you in the old house in Brooklyn. I was interested in your air-ship--Oh, I recognised it for what it was, notwithstanding its oddity and lack of ostensible means for flying--but I was not caught in the whirl of its idea; the idea by which you doubtless expect, and with very good reason too, to revolutionise the science of aviation. But since then I've been thinking it over, and am so filled with your own hopes that either I must have a hand in the finishing and sailing of the one you have yourself constructed, or go to work myself on the hints you have unconsciously given me, and make a car of my own."

Audacity often succeeds where subtler means fail. Orlando, with a curious twist of his strong lip, took hold of the detective's arm and drew him in, shutting and locking the door carefully behind him.

"Now," said he, "you shall tell me what you think you have discovered, to make any ideas of your own available in the manufacture of a superior self-propelling air-ship."

Sweet.w.a.ter who had been so violently wheeled about in entering that he stood with his back to the curtain concealing the car, answered without hesitation.

"You have a device, entirely new so far as I can judge, by which this car can leap at once into s.p.a.ce, hold its own in any direction, and alight again upon any given spot without shock to the machine or danger to the people controlling it."

"Explain the device."

"I will draw it."

"You can?"

"As I see it."

"As you see it!"

"Yes. It's a brilliant idea; I could never have conceived it."

"You believe--"

"I know."

"Sit here. Let's see what you know."

Sweet.w.a.ter sat down at the table the other pointed out, and drawing forward a piece of paper, took up a pencil with an easy air. Brotherson approached and stood at his shoulder. He had taken up his pistol again, why he hardly knew, and as Sweet.w.a.ter began his marks, his fingers tightened on its b.u.t.t till they turned white in the murky lamplight.

"You see," came in easy tones from the stooping draughtsman, "I have an imagination which only needs a slight fillip from a mind like yours to send it in the desired direction. I shall not draw an exact reproduction of your idea, but I think you will see that I understand it very well.

How's that for a start?"

Brotherson looked and hastily drew back. He did not want the other to note his surprise.

"But that is a portion you never saw," he loudly declared.

"No, but I saw this," returned Sweet.w.a.ter, working busily on some curves; "and these gave me the fillip I mentioned. The rest came easily."

Brotherson, in dread of his own anger, threw his pistol to the other end of the shed:

"You knave! You thief!" he furiously cried.

"How so?" asked Sweet.w.a.ter smilingly, rising and looking him calmly in the face. "A thief is one who appropriates another man's goods, or, let us say, another man's ideas. I have appropriated nothing yet. I've only shown you how easily I could do so. Mr. Brotherson, take me in as your a.s.sistant. I will be faithful to you, I swear it. I want to see that machine go up."

"For how many people have you drawn those lines?" thundered the inexorable voice.

"For n.o.body; not for myself even. This is the first time they have left their hiding-place in my brain."

"Can you swear to that?"

"I can and will, if you require it. But you ought to believe my word, sir. I am square as a die in all matters not connected--well, not connected with my profession," he smiled in a burst of that whimsical humour, which not even the seriousness of the moment could quite suppress.

"And what surety have I that you do not consider this very matter of mine as coming within the bounds you speak of?"

"None. But you must trust me that far."

Brotherson surveyed him with an irony which conveyed a very different message to the detective than any he had intended. Then quickly: