This is a book containing two novellas by this author, set in his Revelation Space universe.
For those unfamiliar with Mr Reynolds he is a British former scientist, once part of the European Space Agency, who gave up scientific research to write SF full time.
In the first story, Diamond Dogs, we have two main characters, Richard and his lifelong friend Roland Childe. The two have enjoyed presenting each other with challenges all their life but Roland was assumed dead years age, but one day Roland approaches Richard with a new challenge. At first Richard isnt interested, he's grown past all that but as Roland fills him in about this latest endeavour he finds it hard to resist and so accepts the challenge.
The object of Roland's strange desire is an alien artifact called The Blood Spire, a vast tower floating about the surface of a planet they travel to from Chasm City. The tower consists of a series of rooms, each requiring a test to complete before allowing access. Roland assembles a team including Richard's former wife, chosen for her innate logical ability, who was also believed dead.
The puzzles get more and more difficult, each wrong move punishing the team harder and harder, until blood is spilt, and limbs are lost. One member of the team is Doctor Trintignant, an expert doctor and cyberneticist, infamous for conducting
horrific medical experiments on allegedly unconsenting subjects, and he helps patch the team up as they are injured. Not only do the tests become harder but the doorways become narrower, forcing the team to remove their armour....
This is a kind of maze-of-death story but also very much cutting edge hard SF, somewhat akin to Iain M Banks or Neal Asher, but heavier on the science, and is my favourite of the two.
Turquoise Days is a different kettle of fish. Basically Naqi and her sister are part of a team conducting research on the Pattern Jugglers, strange etheral beings that live in the sea of the planet Turquoise in places called Nodes. Naqi loses her sister near the start as she swims with and is absorbed by them, and Naqi must continue without her. 2 years later a ship arrives bringing deligates from another world who have an interest in a moat that Naqi and her team are building around a Node. Naqi has not swam with the Pattern Jugglers since her sister's death but is suddenly forced to once more, to communicate with her absorbed sister...
An interesting story with a science fantasy feel, Naqi travelling about the world in dirigibles rather than rocket ships-it has a more 'earthy' feel about it, while still being very much future SF.