She was still seated in the armchair she had occupied last night, though now imprisoned beneath a settee that had closed over her like a lid. To her right, through the gap between the two clasped pieces of furniture, a piercing arrow of sunlight warmed her skin.Steampunky novel set in an alternate Raj where Britain has exploited captured extraterrestrial technology to remain Top Nation; protagonist is the daughter of an Indian government minister and his long-dead English wife; she is pursued by various miscreants who wish to overturn British rule for one reason or another; she discovers that the Raj is based on an alien power source, and there is a reckoning. You can get it here.
This was the SF book that had lingered longest unread on my shelves. Next on that pile is Indigo, by Clemens Seitz.
