Riley ran to the door and blew his whistle. Verbeck and Muggs already were at work. Before Riley could instruct the sergeant that a man be detailed to remain at the house while the others followed, Verbeck and Muggs had pulled the heavy table to one side-to find the wire pa.s.sing through a tiny hole in the floor and into the bas.e.m.e.nt.

Verbeck led the way below. The wire was picked up easily, running to an outside wall and through it. On the outside it went up the side of the house, beside a water pipe, thence to a tree near by.

"Follow the wire-and be quick about it!" Riley commanded the sergeant and his men. The police knew only that this had something to do with the pursuit of the Black Star, but the excitement of Verbeck and his companions was infectious, and they went at their work eagerly, sensing that seconds were precious.

Electric torches flashed as they surrounded the tree, and one man prepared to climb.

"There it runs!" Riley shouted. "Flash your lights! See it? To the other tree!"

Thus they crossed the yard to a corner, going from tree to tree, flashing their lamps always on that slim, long-hanging wire.

"Whoever heard of a dictograph wire this long!" Riley exclaimed.

"n.o.body but the Black Star would use it. No telling where it runs-and we haven't a great deal of time! Send back another man, sergeant, to stand by the house and bring us news if there's a telephone call. Send one who can drive Verbeck's roadster to us!"

A man was selected and sent, and the tracing of the wire went on. They came to the corner, and there the wire sprang from a tree to a telephone pole, and across the street to another pole, then to an unimproved block of land, where it ran from tree to tree as before.

Led by Verbeck and Riley, with Muggs at their heels, the police waded through snowdrifts, crashed through wet underbrush, rending the black night with the light of their torches. The wire twisted from tree to tree, never more than a few feet above the ground.

"Whoever laid that wire didn't waste any time," Riley said.

They lost it in a clump of brush, but found it again. Every man of them was wet to the waist now from breaking through the drifts of snow, but their enthusiasm was not dampened.

"We've been half an hour already!" Muggs protested. "How far does this thing run?"

No one took the trouble to answer him. They had crossed the unimproved block at last and reached another street. Once more the wire sprang to the crosspiece of a telephone pole, and across the street to another.

Now it ran along the edge of a private park to a narrow alley, and there it followed the roof line of sheds.

They began exercising some caution now, for there was no telling where the wire would end, or when, and they did not care to stumble on the retreat of the Black Star unprepared for a clash. Muggs, some paces ahead of the others, strained eyes and ears to detect the presence of a foe. Muggs didn't feel sure they had done right in following the wire, but he realized that the tip from the unknown woman was one that could not have been ignored.

At the end of the alley, the wire ran in the direction of a cross street. Here it was suspended from the trees again, but higher, and there was difficulty in following it. It took half an hour to reach the next corner, and there the wire turned back toward Verbeck's house.

"'Tis a quarter after one," Riley said. "There's been no alarm from headquarters, or we'd have had the man coming after us in the roadster. But where the deuce does this wire run?"

Down the street a block, around the corner, went the wire, from tree to tree, now high in the air and now looped low. To the alley again, and down it in the black night! Here, their torches flashing, they followed it from shed to shed, and finally came to where it ran down the side of a garage and so reached the ground. Muggs dug frantically with his hands until the snow had been thrown to one side. The wire ran beneath a board, and half a dozen men sc.r.a.ped snow away until the board could be raised, Verbeck and Riley working frantically and urging on the others.

The board ended at the edge of an iron manhole, and Riley, with a muttered curse, got up from his knees.

"Into the sewer!" he exclaimed. "Into the sewer! Think o' that!"

"It's a fake-we've been done!" Muggs declared.

"'Tis no fake!" Riley protested. "Here's the wire, and we was told to follow it, wasn't we? Into the sewer!"

"Off with that cover!" Verbeck shouted, stepping forward and taking command. "You've forgotten something, Riley. This is the old sewer, and has been used for two or three years as a conduit for gas pipes and electric wires. There's no sewage in it."

Riley's exclamation of relief showed that he had forgotten. Like madmen they worked at the covering of the manhole, smashing the ice around it, tearing at it with their hands until they were raw and bleeding. Presently they hurled it to one side.

"In we go!" Verbeck said. "And let's try to make better time!"

"Easy there! We go-but we go prepared!" Riley said. "I'll go first, if you don't mind, Roger. Some of the Black Star's gentlemen friends might be waiting in this old sewer with implements of destruction to greet us."

He flashed his torch, and lowered himself. A moment later they heard his call, and one by one they slipped from the alley into the big bore in the earth, the last man letting the manhole covering fall into place.

Straight ahead they went now, bending low, dodging elbows of big gas mains, on the alert for uninsulated electric wires. The cement walls were covered with frost, the air was like that of a refrigerator.

They made a turning, and went on, always following the little wire that had been looped along the joints of the gas main. And always they were on the alert, flashing their torches ahead, expecting to be greeted any instant by some show of hostility. They knew the reputation of the Black Star-these men. Perhaps, after all, this was his trick. Perhaps they would find themselves prisoners underground, or face some new peril the master criminal had invented for their discomfiture.

Another curve in the big bore, with Riley stopping them and creeping ahead to peer around the bend, and be sure no danger waited! They made their way along as swiftly as they could now, their teeth chattering, their hands numb with the cold. And now the wire ran to the roof again, along a smaller gas main, and so to another manhole.

"Out again into the night!" Riley grunted. "What do you know about that? Well-let's get after it!"

They got beneath the manhole covering and fought to get it free. It was heartbreaking work, for the covering had a weight of snow above it, and ice filled every crevice. But finally they felt it give, and after a time forced it a short distance to one side, the snow caving in upon them.

Muggs crawled up and dug at the snow! Inch by inch they forced the manhole covering back, and finally they emerged into the open air and closed the covering again. They traced the wire to a tree at the end of the alley, and from there to a telephone pole, and across the street in the usual manner.

They spoke but seldom now. They were almost exhausted; more than one feared they had been hoaxed. Again they flashed their torches and followed the wire, once more across the corner of an unimproved lot, across another street, and then--

"Wh-what?" Riley cried. "Do you see where we are? Back to Verbeck's place-that's what! On the other side of the house!"

He would have said more, but Verbeck's grasp on his arm stopped him.

Into Verbeck's heart had come a sudden fear, and he didn't see the advisability of the sergeant and the police squad knowing everything.

"What kind of a stunt is this?" the sergeant growled.

"Never mind!" Riley counseled sternly, aware of what the end might be.

"We've been following this wire, haven't we? Very well! We had a reason for wanting to know where it ran. And that's all."

The sergeant subsided, but he guessed that it was not all.

They were in the yard of the Verbeck place again now, the wire running from tree to tree as before. Finally it sprang to the side of the house, and down it to a window in a rear room. There Riley, who was leading, stopped.

"That's all for the present, sergeant," he said. "Go inside and get warm-you and the men. If there's been any telephone message, come out and tell us."

The men needed no second invitation to hurry to the fire, and they followed the sergeant rapidly around the corner of the house toward the veranda, leaving Verbeck and Riley and Muggs alone beneath the window.

"Well?" Riley said.

"Follow it!" Verbeck commanded. "It must end somewhere. And we don't need the squad with us when we find the end."

"That's the way I looked at it. Great Scott, what a chase! Through the snow and through the sewer--"

"No message!" the sergeant shouted from the veranda.

Muggs raised the window. They crept over the sill into the dusty room.

Again Riley's torch flashed, and they saw the wire running up the side of the window to the ceiling and through it.

"To the floor above!" Verbeck said.