This book has many of the things I love: Steampunk, electricity, Spring-heeled Jack, werewolves, a mystery, time-travel affecting the present, and the implication of liminal space. It also has a glowing recommendation from Michael Moorcock on the back. Note to self: Do not buy any other book Michael Moorcock likes.
A tale told by an idiot, full of sound and fury, signifying nothing
The Strange Affair of Spring Heeled Jack by Mark Hodder