was nearing her goal and had gone into a long slide when, of a sudden the clip-clip of skates again came to her ears. It was hardly necessary for her to turn about to make sure that the stranger in the long coat had also rounded the island.

For a second she glided on, uncertain what course to take. It was nearing midnight. She was alone on the lagoon, a long way from any habitation. A stranger was following her; why, she could not tell. To throw off her skates and gain the bank before he came up was impossible. She decided, without being greatly alarmed about it, again to circle the island and, if necessary, take a spin the whole length of the lagoon.

CHAPTER IV
TRAPPED IN THE OLD MUSEUM

Florence had little fear for the outcome of this rather amusing adventure. She had been trailed over the ice by possible admirers before. She did not care to allow this one to catch up with her, that was all. She would skim along down to the far end of the lagoon where, a mile and a half away, the dome of the old museum loomed, a black bulk in the dark. She would then make the broad turn which this end of the lagoon afforded. She would have a clear mile and a half in which to put forth her best efforts. Surely she could outdistance the stranger and, with skates off, be away over the slope and down the beach toward the O Moo before he had reached this end of the lagoon once more.

Saving her strength on the down trip, keeping an even distance from the mysterious skater, she glided onward toward the old museum.

Just as she neared the broad end, where she was to make the turn, she glanced back. At that very moment, the flash of a powerful automobile lamp on the park drive a half mile away fell full upon the stranger’s face.

A little cry escaped her lips. This was no mere youthful enthusiast. His was the face of one whom few would trust. At that very moment his visage was twisted into an ugly snarl which said plainer than words:

“Now, young lady, I have you!”

“Why!” she whispered to herself, “that might be the face of a murderer!”

At that same instant, there flashed through her mind the note of warning tacked on the schooner. Perhaps this was the man who had placed it there.

In her consternation, she missed a stroke. One skate struck a crack in the ice; the clamp slipped; the skate went flying; disaster impended.

Florence was not a person to be easily defeated. One instant she had kicked the remaining skate from her foot and the next she was racing away over the glistening ice. She stumbled and all but fell. But, gaining courage from the near-by sloping bank, she plunged on.

Now she was ten yards away, now five. The metal cut-cut of skates behind her grew louder. Redoubling her efforts, she at last flung herself upon the snowy slope, to climb on hands and knees to the crest, then to race across a level space and gain the sheltering shadows of the museum.

It had been a hard struggle. For a few seconds she leaned panting against the wall. One skate was still in her hand. Without thinking why, she tucked this skate into the belt of her coat.

Her mind was in a whirl. What should she do? She was not safe here. For the man to remove his skates and scale the bank required but a moment. They were alone in the frozen park, a mile from any protection she could be sure of. She was not a good runner.

“No,” she whispered, “I couldn’t do it.”

She chanced to glance up, and her lips parted in a suppressed exclamation. There was a window open above her. True, it was some fifteen feet up, but there was an iron grating on the window beneath it.

“If only the grating is not rusted out,” she murmured hopefully, and the next instant she had reached the ledge of brickwork and was shaking the railing vigorously.

“It’ll hold I guess.”

Up she went like a monkey climbing the side of a cage. At the top of this grating there came an agonizing second in which she felt herself in danger of toppling over before she gained her balance on the window ledge above. Her splendid training served her well. She threw herself across the stone casing and, for a few seconds, lay there listening.

Hardly had she dropped noiselessly to the floor, some three feet below, than she heard the thud-thud of hurrying footsteps on the hard-packed snow. Holding her breath, she crouched there motionless, hoping beyond hope that she might hear those footsteps pass on around the building.

In this hope she was disappointed. Like a hound who has lost his scent, the man doubled back, then paused beneath her window.

The girl’s heart raced on. Was she trapped? The man, she felt sure, would, somehow, gain access to the building. Nevertheless, she might escape him.

The building had once been a museum, the central building of a great world exposition. No longer used as a museum, it stood there, an immense, unused structure, slowly dropping into decay. The floor on which she had landed was really a broad balcony with a rusty railing at its edge. From where she crouched she could see down into the main floor where stretched, twining and inter-twining, mile upon mile of rooms and corridors.

Slipping out of her shoes, she buttoned them to her belt, then stole noiselessly along the balcony. Moving ever in the shadow of the wall, she came to a rusty iron stair. Here she paused.

Would the stair creak, give her away? The man might at this moment be in the building on the ground floor. Yet, on this narrow balcony, she was sure sooner or later to be trapped. She must risk it.

Placing one trembling foot on the top step, she allowed her weight to settle upon it. There followed no sound. Breathing more easily, she began the descent. Only once did her heart stand still; a bit of loose plaster, touched by her foot, bounded downward.

She dared not pause. The die was cast.

Once on the ground floor, she sprang across a patch of light and found herself in the shadows once more.

Moving with the greatest possible speed, yet with even greater caution, avoiding bits of plaster, rustling papers and other impediments in her course, she made her way along a wall which to her heightened imagination seemed to stretch on for a mile.

Once as she paused she thought she caught the sound of heavy breathing, followed by a dull thud. “Must have come in through my window,” she decided, and, indeed there appeared to be no other means of access; all the ground floor doors and windows were either heavily shuttered or grated.

“These shutters and gratings,” she told herself, trying to still the fear in her heart by thinking of other things, “are relics of other days. Here millions of dollars worth of relics, curios, and costly jewels were once displayed. Mounted animals and birds, aisle after aisle of them, rooms full of rich furs and costly silks, jewels too in abundance. They’re all gone now, but the shutters are still here and I am trapped. There’s only one exit and that guarded. Well, perhaps another somewhere. Anyway, I can wait. Daylight drives wolves to their dens. If only I can reach the other balcony!”

She had been in the building in the days of its glory, and had visited one of the curators, a friend of her mother. There were, on this other balcony, she remembered, a perfect labyrinth of rooms—cubbyholes and offices. Once she gained access to these she probably would be safe.

But here was another stair. She must go up.

Only