way left to her. Her long silvery-green hair floated on the surface, partially obscuring our view. Still, you could see that she had a woman’s head and a fish’s tail, and that tight ropes bound her arms and torso. In the light of the lantern, her skin was luminous; the scales near the surface glowed.
She wasn’t human. But when I saw the rope cutting into her skin, I bit my lip.
She’s dangerous, I reminded myself. A killer, from what Nat had said. And the rope and the gag didn’t seem to bother anyone else. They were watching the mermaid with dispassionate eyes—all except Penebrygg, who looked upon her with something close to reverence.
“Miraculous,” he breathed. “A true ondine.”
Ondine? I looked up at Nat, who was standing across from me. “I thought you said she was a mermaid?”
“That’s the layman’s term,” Gabriel cut in. “Those of us who have read the great Paracelsus would more properly term her a water elemental—that is, an ondine.”
“Or undine,” Sir Barnaby said.
“Or nymph.” Sir Samuel flourished his cape. “My edition translates the term that way.”
Captain Ellis and the ship’s doctor looked confused. So did the King and the Lord High Admiral.
“Or we might just use the old English term ‘mermaid,’ ” Nat said calmly, “whether or not we’ve read our Paracelsus. Then everyone will understand what we mean.”
“There’s much to be said for that,” Penebrygg agreed, but even in the dim light I could see Gabriel looked a little annoyed. There had never been any love lost between him and Nat.
“I prefer the terminology of Paracelsus,” Gabriel said in his best aristocratic manner. “After all, he was the first one to look at the matter scientifically, to understand that each of the four great elements has its own associated spirits—”
“Ondines for water, salamanders for fire, gnomes for earth, and sylphs for air,” Nat said.
Gabriel raised an eyebrow in surprise. “So you have read him.”
“Yes. An interesting theory,” Nat said. “But short on evidence.”
Gabriel looked as if he were about to argue some more, but Sir Barnaby cut in with a question for the ship’s doctor. “Tell me, how long can she stay down like that?”
“Much longer than a human can.” A slight man with a scholar’s stoop, Dr. Verney consulted his memorandum book. “We’ve clocked her at a maximum of seventeen minutes and twenty seconds. But that was earlier in the day. The periods are noticeably shorter now.”
“Yes.” Deeps had his own timepiece in hand. “The last one was only four minutes and thirty-six seconds.”
“Interesting.” Sir Barnaby leaned forward on his cane to get a better view of the creature. “You think she’s weakening, then?”
When I’d first met Sir Barnaby and his colleagues, they had looked at me in just such a way—as a curiosity, an oddity to be tested. Resentment flickered in me at the memory.
“If she is,” I found myself saying, “maybe it’s because the ropes are tied too tight.”
“Too tight?” The King frowned. “Do you think that’s so, Captain Ellis?”
The captain’s jowly face reddened at the mere idea. “If we loosen them, she’ll thrash herself right out of that barrel and into the sea, and then we’ll all be at her mercy again. She’s a killer.”
“How exactly did she attack you?” I asked.
“She tried to wreck us,” Captain Ellis. “She and her kin. And if Lord Walbrook hadn’t been so quick-witted, they would’ve succeeded.”
“Kin? You mean you saw more than one mermaid?” Penebrygg asked.
“Three by my count,” volunteered Dr. Verney.
“By mine, too,” Captain Ellis said.
“And this was near the mouth of the Thames, was it not?” the Lord High Admiral put in. “A treacherous place at the best of times, with sandbars and strange currents. A man must know what he is doing to get by them.”
“Yes, my lord.” Turning to me, Captain Ellis said, “I can show you the place later on the map, if you like.”
“And when did it happen?” I asked.
“This morning, just after dawn.” The captain’s voice turned grim. “I was steering the ship myself, with my best hands to help me. That’s when we heard the singing.”
“I heard it too,” the ship’s doctor said. “Such exquisite music—I have never heard the like.” He glanced shyly at me. “Though I have never heard a Chantress sing.”
“They’re nothing alike,” Nat assured him. “Chantress songs sound rather uncanny to our ears.”
Norrie had always said they sounded eerie. I’d never known before what Nat thought.
“But the mermaids’ song was beautiful beyond words,” Nat went on. “Beautiful enough to drive men mad,