The Hydrogen Sonata

by Iain Banks

The Gzilt, a civilisation that almost joined the Culture 10,000 years before the novel, have decided to Sublime, leaving behind “the Real” to take up residence in higher dimensions. The Zihdren-Remnant, what is left of an older species that Sublimed before the Culture was formed, send an envoy to confess a long-kept secret before the Gzilt depart but a Gzilt warship intercepts and destroys their ship several weeks before the Sublimation is due to take place in order to preserve that secret.

The Culture sends ships both to wish the Gzilt well, as they have always been on good terms with the Gzilt, and to keep an eye on the younger species arriving to scavenge the technology and infrastructure the Gzilt leave behind. Two of these, the Liseiden (an eel-like species) and the Ronte (a hive insect-like species) are jockeying in negotiations with the Gzilt for official permission and preferred status.

Vyr Cossont is introduced as a former Lieutenant-Commander (reserve) of the Gzilt, who has set herself a life-task of playing T. C. Vilabier's 26th Strong-Specific Sonata For An Instrument Yet To Be Invented, the eponymous Hydrogen Sonata, on the instrument subsequently invented for its performance: the Antagonistic Undecagonstring, or elevenstring. In order to do so, she has had to grow two additonal arms. Both the instrument and the work are presented as unusually challenging.

Spyware aboard the Gzilt warship has transmitted the secret to the 14th Regiment, traditional opponents of the current power structure and erstwhile dissenters in the decision to Sublime; they recruit Cossont, a four-armed musician and now a civilian who once knew Ngaroe QiRia, a Culture citizen who can verify the truth of the Zihdren secret. Alerted to their knowledge and doing all he can to ensure a smooth Sublimation, Septame Banstegeyn orders their destruction. Cossont barely escapes, and is eventually picked up by the Mistake Not…, a Culture ship of non-standard class. They begin to head towards the storage facility where Cossont left the mind state QiRia had given her, but are interrupted by intelligence that he had stopped at Xown, where Cossont had been living, some five years earlier. Despite confirmation that he had indeed stopped there, they are unable to locate the information they need.

Meanwhile, a group of Minds dealing with the issue wake Scoaliera Tefwe, a former lover of QiRia who has been Stored for many centuries. She agrees to try and track him down, and her mind state is sent to inhabit a ship avatar, stopping for information from an old drone. When she finds him, he reveals he has had the memories removed and left them somewhere safe.

Cossont and the Mistake Not... successfully retrieve QiRia’s mind-state, but only after being attacked in the storage facility on Banstegeyn’s orders. Unfortunately, the memories have also been wiped from the mind state, and they have to return to Xown when they realise where they have been hidden. Cossont manages to retrieve the memories despite heavy attack and the loss of the ship’s avatar.

The Gzilt Book of Truth is revealed to have been a sociological experiment by a fringe Zihdren scientist that was subsequently forgotten. This had been disclosed to QiRia and other members of the prospective Culture. After finding this out and deciding it would not affect the ability of the Gzilt to join the Culture being formed, their minds had been wiped of these memories. However, experimental memory storage augmentation in QiRia prevented the memories from being properly removed.

The other Minds in the group decide to keep the secret, and some 99.9% of the Gzilt Sublime. Cossont is one of the few that does not. She leaves behind her elevenstring instrument to go back to the Mistake Not... with the apparent intention of visiting QiRia at the planet where he is on retreat and returning his memories.