Time Scout by Robert Asprin & Linda Evans

Another shock shook them. A rock nobody’d seen. The whole raft shuddered, bounced off, rocked sideways over a lip of water, dropped sickeningly. The impact jarred her breath out, then they plunged on. She had no idea half the time if she faced upriver or down. Another jolt shook the raft It can’t take much more of this, it’ll come apart on us …

The raft lurched-then either it or Margo was abruptly airborne. Margo screamed. She came down in the water. The muddy Limpopo closed over her head. Margo fought to find her lifeline. The current was savage. She couldn’t move against it She swallowed water, strangled, knew that if she hit a submerged rock, she would die.

Her face broke the surface. She was moving…

Kynan Rhys Gower grabbed her hair and pulled. Margo groped for his arm, his waist. She slithered forward into his lap. The raft rocked violently, spun in a new direction …

Then quieted.

They still raced through the darkness like a cork over Niagara Falls, but they’d made it alive through the rapids.

Margo quietly threw up in Kynan’s lap, disgorging the water she’d swallowed. He pounded her back, helping her cough it out. Then he helped her sit up and made sure she’d suffered no broken bones. Margo winced a few times, but the worst she’d endured was bruises. Koot watched silently.

She finally met Kynan’s gaze. “Thank you.”

The Welshman pointed to himself then the river, then pointed to her and the river.

”Yes,” she shivered. “We’re even now. Thank you, anyway.”

He spread his hands and shrugged, then busied himself checking for damage. Koot watched her without speaking.