Tim Powers The Anubis Gates is pure poetry and magic. I tried to follow all the transformations and soul-communications for a while but it just got too crowded in my mind. It would've been like watching a fireworks show and trying for each burst to assign a set of coordinates to the explosion. It all just happens too quickly, and to do so would be against the spirit of the story anyway.
The spirit of that story does not shy away from the physically repugnant, the gory, from blood, injury, distress, and trauma. These are essential components of it, alongside an incredibly inventive cast of spells and magical devices, characters and time-travel trajectories. The time-travel aspect is very tightly conceived and executed, and it relies upon a river trope.
Time is essentially a river frozen over, but the frozen sheet has holes, through which one can 'cheat' time. In other words, travel through time. Backward time travel is fairly easily achieved, but forward travel is bloodier and much more complicated, involving here the use of a ka to jump forward through bodies across generations, which is obviously a much slower process.
This is all tied to Egypt, magic, and London, and there is travel across space as well as time in order to set in motion a series of jumps, backwards and forwards, all in the name of Romanelli and a Master who control goodly sections of time and have gangs of henchmen all over the place (time) to keep an eye on the use of the various (time) holes.
All of this is really beside the point, because reading the book you are swept into a series of action-sequences that lasts hundreds of pages and involves all kinds of spells being cast, counter-spells, evasions, near-misses, bloody hits, deformations, and deflations (of the ka) amongst a few characters that we follow. But it's hard to keep track because they keep switching bodies.
It's really a lovely book, and it actually starts out pretty straightforwardly as a kind of group-back-to-the-future science experiment that predictably goes wrong. There is, however, nothing predictable about this book which, it has been claimed, is one of the very first 'steampunk' novels ever written. Herein, I think, lies its real appeal. It is not a straight historical novel.
Nowadays steampunk is a set of fashions or genre expectations, but it is really a kind of philosophy (I would argue). It is a comment upon and counter-mapping of the past and as such it is one of the most critical forms of speculative fiction. It explores what might have been had certain technologies existed earlier in time than how we know them to have appeared. It is therefore ontological.
The epistemology comes into how that situation is rendered fictionally, into a world, and as a representation. So, in Gibson and Sterling's The Difference Engine we follow some very famous characters around the world of London in the mid-1800s with Darwin and Lyell and Huxley introducing their ideas, but we also have functioning computers.
How that plays out is seen through the eyes of various characters, but it is also apparent in the architectures, in the streets, and in the ambitions and political beliefs of the (mostly famous) people teeming through the pages of the novel. In The Anubis Gates, we follow Coleridge and Byron around for a while, seeing things they may or may not have seen, but with magic and poetry alive.
We also have casts of incredible characters, including gangs of beggars led by an evil clown on stilts who meet in the sewers to discuss the state of street politics, finances, and power. The underground spaces are vast and strung across with massive hammocks, jails, and waterways all dimly lit and traversed at one point or another during various struggles that take place.
The structure is innovative, and it first jumps backwards in a series of steps, out of that first jump out of a fairly normal post-magic present, at one point to the coldest winter London has known for centuries, where accents change, and chases (of course) take place; we then have from there a series jumps forward, and people become unmoored. They start to float and hang sideways from chains.
It is an incredible thing to behold, this novel. It is getting me to think about modern post-Tolkien fantasy a lot, and I've added some Moorcock and some Harrison to my must-read pile, all part of the Gollancz Fantasy Masterworks series.