"It being a rented house, I did not look for any such trap as this,"

said he. "Furthermore, I did not believe that Cervera had any warning of my coming, and I felt satisfied that she was alone here. Have you seen anything of Venner while waiting in the cab?"

"Not a sign of him."

"It's odds, then, that he was here when I arrived, and made his escape by a back door," growled Nick. "If so, it goes to show that he is in with her and the Kilgore push, and not a blind victim to their cunning.

We now must get some proof of that, Chick, and force that gang and their game to light. We at least have made a beginning, and now for another move."

"To-night?"

"At once!" declared Nick. "Cervera must find shelter somewhere, and it's very likely she will go to Venner's house. That must be our next point, and we will lose no time. Possibly we yet may land her before she finds cover."

"We can give it a try," cried Chick.

"Help me extinguish these lights, and then we'll be off again."

"I'm with you."

"What sent you into the house so suddenly?"

"The reports of your revolver," explained Chick. "I at once recognized its bark, and knew something was wrong."

"Ah! I see."

"I saw the light in the chamber, and supposed you might be letting the woman prepare to go with you," added Chick. "That was while I sat in the cab. But when I heard your gun, I smashed open the front door and bolted upstairs."

"Very lucky, too," nodded Nick. "That she-devil would have burned the house, and me in the bargain. But the end is not yet."

"Well, hardly!" laughed Chick, as they descended the front stairs and extinguished the last light.

"We'll stop an officer, and send him here to watch the house," said Nick. "Then we'll have a look at Venner's dwelling. It's my opinion, Chick, that our work has now begun in good earnest."

"Well, I reckon we shall prove equal to it," smiled Chick, rather grimly, as they hastened to enter the waiting carriage.

CHAPTER XV.

THE DIAMOND PLANT.

"This does settle it!"

"What do you mean, Dave?"

"It must be done?"

"We must get these Carters--that's what! If we don't get them, Spotty--you take my word for it--they'll get us!"

"Do you really think so, Dave?"

"Not think, but know so!" declared Kilgore, with emphasis. "I know these Carters, root and branch. They have now struck our trail, and they'll stick to it like bloodhounds till they run us down--unless we get them!

It must be done, I say, and done promptly."

"Put them down and out?"

"Exactly. It's them--or us!"

"And why do you think, all of a sudden, Dave, that Nick Carter is so hot on our heels?"

"I'll tell you why, Spotty."

And Mr. David Kilgore, chief of the notorious diamond gang bearing his name, and one of the keenest and coolest criminals in or out of prison walls, removed his pipe from his mouth and his heels from the edge of the table, and drew forward in his chair to explain.

It was a curious place, that in which the speakers of the above were seated, in the bright glare of an electric light.

It was inclosed with four solid stone walls, with not a window or aperture through which a ray of light could be detected from outside.

Yet in one of the walls was a low, narrow door, also of stone, and so cleverly constructed and fitted that, when swung into place in the wall, it was comparatively beyond the detection of anybody ignorant of its existence. This door then stood open, but the aperture through the wall was heavily curtained.

Three of these walls formed the original foundation of an old and extensive suburban mansion, the location, ownership and present use of which will presently appear. The fourth wall, that with the door, was of more recent construction, and was built squarely across the original cellar of the house. It had been made to mask this secret subterranean chamber in which the Kilgore gang was then gathered.

The place was commodious, and contained some noteworthy objects. In one corner was a powerful hydraulic press. Near by was a splendid electrical furnace, capable of generating an extraordinary degree of heat. Against the adjoining wall were several barrels of sulphur, of which only one was unheaded. Near by was a large box of anthracite coal, black and glistening in the rays of the arc light.

Parallel with the opposite wall was a workbench, laden with curious retorts, crucibles, test tubes, metal molds, and no end of tools, all of which plainly suggested the work of one versed both in chemistry and some mechanical art.

In the middle of the room was a square deal table, at which Kilgore was seated, with Matt Stall and Spotty Dalton, the original three of the Kilgore gang.

Two other persons were present, however, and they were engaged in examining some work on the bench mentioned.

One of them was a tall, angular Frenchman, about sixty years of age, named Jean Pylotte. He had a slender figure, somewhat bowed; but his head was ma.s.sive, in which his gleaming, gray eyes were deeply sunk, like those of a tireless student and hard worker.

His companion at the bench just then was Sanetta Cervera, the Spanish dancer--the murderess of Mary Barton--the vicious dare-devil who had served Nick Carter one of her evil tricks that very evening.

Cervera had arrived at the diamond plant less than an hour before, and had hurriedly told her confederates the whole story of her crime and her adventure with Nick.

Crime was too common with these outlaws, however, and loyalty to one another too natural, for Kilgore to censure his only female confederate very severely. Yet as Kilgore now proceeded to explain, her crime had rendered their situation decidedly more alarming.

"I'll tell you why these Carters are now to be seriously feared," said he, nodding grimly at his hearers. "This last move of Cervera has hurt us severely."

"In what way?" demanded Spotty Dalton, the pock-marked chap who had relieved Venner's partner of the Hafferman diamonds about two weeks before. "I don't see just how, Dave."

"No more do I," put in Matt Stall.

"You'll see," replied Kilgore, "when I run over a few facts which led to our being here, and at work on our present game."

"Well, Dave, we're listening."

"One year ago we three were in Amsterdam, Holland, weren't we?"