1,800 m – 3,200 m · pelagine

Mantle-singer

A large, slow-moving organism of the lower Twilight Belt associated with Pelagine settlements, recognised by the survey for its structured low-frequency vocalisations.

The hull registered the singer before any instrument did. A vibration through the seat, then through the floor, then — minutes later — a reading on the hydrophone trace. The seat reads it before the trace does, which is the order I have learned to trust at this depth.

The survey does not claim to know what the mantle-singer is. The term is the author's, adopted from a description offered, in translation, by a Tyrian Court interlocutor who used a word the translators rendered approximately as one who speaks to the mantle — meaning the deep, the pressure, the column of water itself. Whether this is biology, occupation, or title is not clear. The survey has used the word as a name and will continue to do so with reservations.

What the survey does know: there are large, slow organisms in the lower Twilight Belt that produce structured low-frequency sound. The structure is reproducible. It is not random biological noise. At frequencies between twelve and forty hertz, the sound carries laterally for distances the survey has not been able to fully measure. Submersible hull contact registers the vibration as a physical sensation before instrumentation reads it.

As understood by the author

The mantle-singer's body, as best resolved by sonar and by submersible observation at distance, is elongated, with a largest dimension estimated at six to fifteen metres. It does not hold still. It moves through the water column with a slow oscillation. It has not approached a submersible directly. When illuminated by a wide survey beam, it has altered course — not in alarm, as far as can be told, but in the manner of an animal that has registered a thing and found it unremarkable.

Standing

The Tyrian Court's record, such as has been translated, does not classify the mantle-singer as fauna. The Court has not elaborated on this, and the survey has not pressed the question. It is noted here and left open.

The Court's translators did not call it an animal. I have used the word organism throughout, and the word continues not to fit. I have left it.