The world will never be the same again.
It is 1812, and Napoleon has taken Moscow, by dint of one of the most powerful and subtle sourceries his alchemists have devised. Instead of writing music, the composer Dimitri Bortniansky is working on his memoirs of the fall of the Rodina.
It's another world. The law of similarity and the power of belief allow man to shape things by will and word alone. But it takes a lot of people's belief to power a simple spell, and so it is phrase, fable, superstition and proverb that are the basis of magic. But industry and science are working hard to understand just what works, and how machines can aid the words of magic. A revolution has begun, and there is no going back.
Napoleon's France has grown powerful on the back of its great cloud mining machines, and the wealth of silver they give him. Using his silver he builds the largest army Europe has known, and hires its greatest magicians and alchemists. He has a plan, to invade Russia in the darkest deepest Winter, when the Russians wil be least expecting him. But he needs to control the weather in order to win.
Inspired by English folklore he realises that the powers that shape the world have negative as well as positive effects. If one swallow doesn't make a summer, then a certain number must do so. His alchemists must find that critical number, and give him a way of bringing those swallows, alive, into the Russian winter, turning it into the summer his men need to win.
They succeed. The army marches, the Rodina falls, and the world changes for ever. The code Napoleon grows ever stronger, its words writ into the lives of millions across Europe - an invisible silver chain that holds everyone locked into an eternal swallow-powered summer.
It is paradise and prison all in one.