I just read "Dark Matter," which puts the character of Isaac Newton in a Sherlock Holmes-type role, so when I realized I had another book featuring Mr. Newton, I decided to compare and contrast.
Well, this book isn't so much about Isaac Newton. It's actually more about Ben Franklin. (!) But then again... it's not really about Ben Franklin. I tend, in general, to dislike books that name-check famous historical characters to the extent that this one does, but it didn't bother me in this book. It took a little bit to figure out why, but I believe it's because they really came across as characters in a fantasy novel, not actual historical figures. It was so far-fetched that discrepancies didn't bother me.
As a fantasy novel, I really enjoyed the book.
It's an alternate-history/steampunk setting. The premise is that in 1681, Isaac Newton made a scientific/alchemical discovery (of 'philosopher's mercury') which enabled various innovations - artificial lighting, aetherschreibers (which enable long-distance communications), etc.
Now, in 1715, the discovery may also enable a weapon of indescribable power - and France may use that weapon to wipe England off the map.
A complex and fantastic story ensues, replete with plots, innovations and derring-do. A young Ben Franklin is the principal character, but a brilliant female mathematician at the French court is an excellent counterpoint. Good fun. Not as good as Keyes' 'Thorn and Bone' epic, though.