“Brute information, you mean?”

“Normal human curiosity, I’d call it.”

“Well, don’t go swimming. That’s something I do know.”

“Why not? Ocean acid, or something?”

“Yes, as it happens, but that’s not the main problem. There’s continuous seismic activity at the ocean bottom, and if you swim without armor you’re lucky to last five minutes without suffering the fate of a dynamited fish. There’s enough carbon monoxide in the air to kill you in minutes, enough carbon dust to hinder visual communication seriously, and enough ionized haze to block practically any e-m communication. A lot of my friends think they picked that world because no one else would want it. There must be some reason they don’t get rid of the CO—even I can think of pseudolife genera able to do that in a few decades. You’re a historian, you say; maybe you can find out while you’re poking around.”

The navigator stopped talking and began to manipulate controls.

Three-quarters of an hour later, Hi-Vac was hovering two thousand kilometers above the surface of the larger planet. As promised, a fairly bright reflecting belt and a roughly circular patch of white ninety degrees from it gave locations for the permanent rain and ice regions. The blurred reflection of the suns was no help; its position on the disk told about where Hi-Vac was orbiting but gave no information about anything on Kainui’s liquid surface. Mike couldn’t tell by eye whether he was looking at water or fog; he might or might not be seeing surface. The ship, under power of course, was slowly circling the planet at about thirty degrees south latitude, so the north polar cap was not visible.