nick carter moved with the quickness of a cat. in a twinkling he had jerked the ear piece away and slipped it into his pocket. while doing so, he had straightened up noiselessly and started along the platform of the fire escape in the direction of his own window.

it was a close shave. follansbee had started to raise the shade before nick even reached the railing over which he had to climb, and while he was crawling over the barrier the sash of stone’s window was being lifted.

fortunately for him, however, follansbee tried to make as little noise as possible, consequently his movements were slower than they otherwise would have been. for all that, though, the detective was not out of sight by the time follansbee stuck his head and shoulders through the opening.

it was a tense moment, and nick’s heart skipped a beat or two. should follansbee happen to glance that way the first thing and catch a glimpse of his feet disappearing through the window the consequences would be disastrous.

despite the temptation to do so, he did not forget his caution for a moment, or allow his extreme haste to betray him into a clumsy move. he slipped from view almost noiselessly, and tiptoed away from his window into the shadows of his room.

all the time he was listening intently for some evidence that follansbee had seen him, but none came. seemingly the physician continued to climb through stone’s window, and, having done so, proceeded on his stealthy way down the fire escape.

the detective heard a slight sound, followed by the grating of the sash. evidently the ex-miner had again closed the window.

as soon as nick dared, he ventured back and stealthily peered over his own sill. follansbee was then descending the painter’s ladder. and when the bottom was reached, he lifted the ladder carefully away from the lower platform of the fire escape and carried it, with considerable difficulty, back to the place from which it had been taken.

subsequently his figure vanished, going in the direction of the open end of the court.

“the end of the first act,” thought nick, “and the play promises to be a hair-raiser.”

with his brows drawn together and his arms folded across his breast, he paced softly up and down his room, turning his discoveries over and over in his mind. he had heard enough to realize that crawford was in deadly peril. with his usual cunning, stephen follansbee had again taken what promised to be a perfectly, safe course. to the specialist’s crooked brain, there could be no possible chance of fixing the contemplated crime on him, if it was stone, the tool, who was playing the principal part.

to be sure, nick had overheard a conversation which left him in no doubt as to where the real responsibility lay. he had heard follansbee say that as a result of the proposed measures, crawford would be dead before the twenty-seventh. to the uninitiated, that would have seemed conclusive, and more than enough to convict the physician. nick carter knew better, however; at any rate, he knew enough to be sure that follansbee would make a great fight if the case ever came to trial, and might easily wriggle out of it.

in the first place, he was a distinguished man, a leading light in his profession, and the ruling spirit of a great hospital. nick was the only witness, and it would be very hard, if not impossible, for the detective, with all his reputation, to convince a jury on the strength of such evidence alone that doctor stephen follansbee would stoop to become the accessory to a murder.

follansbee would have the advantage of dealing with a demented man, and could insist that everything which seemed suspicious about his actions—the use of the fire escape and all—had been due to that fact. in other words, he might build up a plausible excuse on the theory that he had been humoring stone in order to study his case, and to see how far the miner’s insanity would carry him.

“it must be the germ of some deadly disease, characteristic of the tropics,” nick told himself, “and he has left the hypodermic syringe there for stone to use. that’s as plain as the nose on my face. but without more evidence than i now have, i can’t be sure of securing a conviction. follansbee is as shrewd as they make them. i wouldn’t be a bit surprised to have him claim that the contents of the syringe were harmless, and that he was merely ‘stringing’ stone for some medical reason. what he said about crawford’s death could always be attributed to the same motive, and his reputation is so great that it would probably hypnotize a jury into accepting his word for it. he’s a cunning rascal, and no mistake. how am i going to manage this affair? i’ve got to do something before two-thirty, but what?”

it was seldom that nick carter felt at a loss, yet he realized that his position was a peculiarly difficult one. he might have forced his way into james stone’s room, of course, but he felt that the mine owner would have sufficient cunning to destroy at once the only tangible evidence of guilt as soon as he heard the first alarm. and even if he did foil stone’s attempt that night, the detective feared that it would only be putting off the evil day. he could have stone locked up, to be sure, and an inquiry into his sanity begun. he might also be able to secure follansbee’s arrest.

that would seem to clear the way and remove crawford’s danger; but the detective saw further than that. he felt certain that follansbee must have demanded a large fee of stone, either for treatment or frankly for the services of getting rid of the man’s partner. furthermore, he was assured that follansbee had contrived it so that the fee would be paid whatever happened.

in that case the arrest or death would by no means end the matter. follansbee’s professional standing would undoubtedly result in an arrangement whereby the specialist would go free under heavy bonds pending his trial, and the moment he was at liberty to do so, he would almost certainly begin work on a new attempt to get rid of winthrop crawford and to earn his money.

that fact had to be taken into consideration in connection with follansbee, for the latter would not be treated as an ordinary criminal; therefore, it became increasingly evident that nick would have to meet cunning with cunning if he hoped to handle the affair successfully.

at last, the hint of a plan came to him. he halted by his window and looked out again. the light was still shining in stone’s room. “i must go in there without the fellow’s knowledge,” he thought. “a minute, possibly half a minute, would do, with good luck. i wonder how i can manage it, though?”