"Don’t forget," said Johannes, raising his hand, "Coldwine’s High Kettai Grammatology is a standard reference book. There aren’t that many textbooks for High Kettai…" He shook his head. "Weird, difficult language. But of those that there are, Coldwine’s is one of the best. If she weren’t on board, if Turgan or someone else had to translate this, they’d probably spend most of their time referring to her damn book anyway."

His hands were jerking in aggressive, choppy movements.

"She’s translated into Ragamoll, obviously," he said, "but it’s easy enough to render that into Salt. But, look, the translation is not the most exciting thing here. Maybe I’ve not been clear… Aum’s not Kettai. We couldn’t visit a Kettai scientist, obviously. Kohnid’s way off our route, and Armada wouldn’t be safe in those seas… but Kruach Aum’s not from Kohnid. He’s anophelii. Their island’s a thousand miles south. And there’s every chance he’s alive.

It brought them up short.

Johannes nodded slowly. "What we have here," he continued, "is invaluable. We have a description of the process, the effects, we have confirmation of the area involved-all those things. But unfortunately Aum’s footnotes and calculations are missing-as I said, the text is badly damaged. So what we have is merely the… the lay description. The science is missing.

"We’re heading for a sinkhole some way off the southern coast of Gnurr Kett. Now, I’ve checked with a couple of cactacae ex of Dreer Samher, who used to deal with the anophelii: where we’re going, we’ll only be a couple of hundred miles from the anophelii island." He paused, aware that he was speaking too quickly in his excitement.

"Obviously," he went on, more slowly, "we could continue as previously planned. In which case we know roughly where we’re going; we know more or less the kind of power involved in the summoning; we have some idea of the thaumaturgy involved… And we could risk it.

"But we couldgo to the island. A landing party. Tintinnabulum, some of our scientists, one or other or both of you." He looked at the Lovers.

"We’d need Bellis to translate," he went on. "The cactacae who’ve been there can’t help us: when they traded it was all hand signs and head shaking, apparently, but obviously some of the anophelii speak High Kettai. We’d need guards-and engineers, because we’re going to have to start thinking about containment for the avanc. And… we find Aum."

He sat back, aware that it was not one iota as simple as he had presented it, but still he felt excited.

"In the very worst case," he said, "Aum’s dead. In which case we’ve lost nothing. Perhaps there’ll be others there, who remember him, who can help us."