As Penny watched the boat, she took new hope. If only she could signal Captain Barker or Sally! Unless the ferry changed course, it was almost certain to pa.s.s the gra.s.s patch. However, with the water shallow there, it would give the area a wide berth.

"Even if I shouted for help, no one aboard would hear me," she reasoned.

"But I'll have to try something! I'm finished if I stay here."

Straight up the river came the _Queen_. Penny could see a man in the lighted pilot house, but no one was visible on the decks. The ferry was traveling at a rapid speed.

Penny decided to wait no longer. Creeping to the very edge of the gra.s.s, she ducked under water, and started to swim. Her strength had gone even more than she realized. Arms and legs were so stiff they barely could press against the water as she stroked. A few feet and she was forced to come to the surface.

"There she is!" shouted Sweeper Joe. Bringing the boat around, he started directly for her.

Penny swam with all the power at her command, stroking deep and fast. Not daring to look back, she could hear the dip of Sweeper Joe's oars.

Straight toward the deepest part of the channel, she propelled herself.

Her crawl strokes were jerky, but they carried her along. And she had calculated well. Aided by the current, she would intercept the path of the oncoming _River Queen_.

From the water, the ferryboat looked like an immense monster as it steamed majestically up the river. Not wishing to attract attention to himself or his companions, Joe shipped his oars and temporarily gave up the chase. But he remained close by, watching alertly. Should the ferryboat fail to see or pick up Penny, he would be after her upon the instant.

Treading water, the girl shouted for help and waved an arm. Her voice was weak even to her own ears, and could not possibly carry to the pilot house of the _Queen_. Would her frantic signals be seen? The night was dark, and she was not yet in the arc of the vessel's lights.

Penny swam a few more strokes, then treaded water again, and signaled frantically. The _River Queen_ did not slacken speed.

"They haven't seen me!" she thought desperately. "It's useless."

Now a new danger presented itself. The _Queen_ had swerved slightly so that Penny was directly in its path. Still she had not been seen. Looming up in gigantic proportions above her, the ferry threatened to run her down.

CHAPTER 21 _RESCUE_

Fearful that she would be killed, Penny screamed and waved. Straight on steamed the _River Queen_, so close now that she could see Sally Barker on the starboard deck. But the girl was gazing away from her, toward Sweeper Joe and the other drifting boat.

"Help! Help!" screamed Penny in one last desperate attempt to save herself.

Her cry carried, for she saw Sally whirl around and stare intently at the dark water ahead. Then she shouted an order to her father. There came a clanging of bells, and the _Queen_ swerved to port, missing Penny by a scant ten feet.

Great waves engulfed her, and she fought to keep above the surface. Her strength was practically gone. She rolled over on her back, gasping for breath.

Then she saw that the _Queen_ had greatly reduced speed and was turning back on her course. A lifeboat also was being lowered.

"They're going to pick me up!" Penny thought, nearly overcome by relief.

The next minute Sally and a sailor were pulling her into the boat.

"Why, it's Penny! And she's half drowned!" she heard her friend exclaim.

Then she knew no more.

When she opened her eyes, Penny found herself in a warm, comfortable bed.

Sally stood beside her with a cup of steaming hot soup.

"You're coming around fine," she praised. "Drink this! Then you'll feel better."

Penny pulled herself up on an elbow and took a swallow of the soup. It was good and warmed her chilled body. She gulped the cupful down.

"Sally--"

"Better not try to talk too much now," Sally advised kindly. "How did you get into the water?"

The question aroused Penny, bringing back a flood of memories. She suddenly realized that she was in Sally's cabin on the _River Queen_ and the ferry was moving.

"Where are we?" she asked.

"You're safe," Sally said soothingly. "You were swimming in the river. We nearly ran you down. Lucky I saw you just in time and we picked you up."

"Yes, I know," Penny agreed. "But _where_ are we? Near the Harpers?"

"Oh, no, we pa.s.sed their place long ago. We're far upriver."

Penny struggled up, swinging her feet out of the bunk. She saw then that she was wearing a pair of Sally's pajamas, and that her own wet garments hung over a chair.

"We must turn back!" she cried. "Tell Captain Barker, please! Oh, it's vitally important, Sally!"

Sally was maddeningly deliberate.

"Now don't get excited, Penny," she advised. "Everything will be all right."

Penny resisted as Sally tried to push her back into bed. "You don't understand!" she protested. "Sweeper Joe, Claude Harper, and Clark Clayton are expecting to make their get-away tonight. They're the ones who have been stealing bra.s.s from the Gandiss factory. It's all cached in the bas.e.m.e.nt of the Harper house--or was unless they've dumped it."

"Penny, are you straight in your head? You know what you're saying?"

"I certainly do! I went there this afternoon. When I learned too much, they tried to hold me prisoner. I escaped by the river--hid in the gra.s.s patch. But they followed me there, and were about to get me, when the _River Queen_ steamed by."

"I did see two small boats there. Just before you shouted I wondered what they would be doing at this time of night."

"Sweeper Joe and Clark Clayton have been dumping the stolen bra.s.s! Unless police stop them before they dispose of it all, not a sc.r.a.p of evidence will be left! All those men expect to leave town tonight!"

"Thank heavens, we have a ship-to-sh.o.r.e radio telephone!" Sally cried, thoroughly aroused. "I'll have Pop call the police right away!"

She bolted out the cabin door.

Every muscle and joint in Penny's body ached, but there was no time to think of her misery. Her own clothes could not be put on. Searching in Sally's wardrobe, she found a sweater and a skirt, and undergarments she needed. By the time her friend returned, she was dressed.

"Penny, you shouldn't have gotten up!" Sally protested quickly.

"I can't afford to miss the excitement," Penny grinned. "Hope you don't mind lending me some of your clothes."

"Of course not, and if you must stay up, you'll need a pair of shoes."