Brennan, Marie -- A Star Shall Fall

The London elves have survived into Newton's lifetime. Now human scientists are trying to figure out faerie-land. The proximate threat is Halley's Comet, which is a threat because the elves made a serious mistake 75 years ago. (Nobody told them then that the thing was periodic.) This is a pretty cool rendition of the science-vs-magic dialectic, but I'm really just hanging on until the sequels reach WW2.

Books I have acquired recently
All the books I own