The structure was large, built up of chunks of coral and other objects. It took up one entire side of the wheelhouse, blocking the port-side windows, extending the full height of the wheelhouse and from one end of it to the other.

None of them spoke as the submersible circled above it. It had to pan over separate parts of the structure, unable to take it all in at once.

Many of the coral chunks were worked—shaped to fit into one another in places, but also etched on their surfaces with shapes that, on the rough coral and underwater, could not be picked out.

The thirty or so human skulls embedded in the structure provided a better surface. The bone was deeply etched all over, and the etched forms were filled in with a dark substance. The lines stood out black against the white of bone—interlocking shapes in which Ha saw several she recognized as having flashed across the skin of one of the octopuses. Here, though, there was no linear sequence—just forms fitted within forms, a pattern of meshed symbols laced across the curves of maxilla, foramen, septum. Each skull slotted into the carved coral wall was a work of careful art, each different from the others. The spacing between them was uneven, but hinted at symmetry, at a logic that might emerge with more examination.

The submersible had been hovering there for a minute or more when the pale arm wrapped across its camera.

There was a confused jumble of images, suckers up close, and then the electronic scramble of short circuit as the submersible’s hull was breached by salt water and it died.

For a long time, none of them spoke. It was quiet enough, in the hotel lobby, to hear the breakers on the sand—even to hear the sound of the breakers, like a gentle inhale, as they drew back into the sea between each surge, the hiss of the sand between each pulse of wave along the tideline.

“A graveyard,” Dr. Mínervudóttir-Chan finally said.

“No,” Ha said. “An altar.”

Chapter 44

Science, at least as we know it, has its limits. In the end, it cannot see into all aspects of reality. One’s inner life, personal knowledge, and sense of meaning are mysteries into which science can only partially penetrate. What seems most impenetrable at present is the brute fact of consciousness: the fact that we once were not, and now are, and are aware of being, and are having a first-person experience in the world which is real—and yet somehow unquantifiable by any means currently available.

—Dr. Ha Nguyen, How Oceans Think

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