A Calculus of Angels is the second novel in Keyes' Age of Unreason series, which features an alternate history postulating that the inquiring minds of the Eighteenth Century developed a rational science of mysticism and spiritual control in the place of purely physical science. The very title of the series is a bit of a misnomer, as the experimental processes described in the books are every bit as rational and methodical as those used in our modern science, indeed, they are more so than the educated guesswork which too often passes for science these days.

Style: Keyes is a good writer, with an extensive vocabulary and a lack of inclination to engage in excessively flowery prose, unlike many other writers using eighteenth-century settings. He clearly has some knowledge of military history, so I was disappointed to find the sections involving action and combat were not quite up to the same elevated writing level as some of the other sections. With the exception of some dialogue, he does not use many stylistic measures to distinguish between different characters and environments.

Story:The central plot revolves around the Russian Emperor's attempt to complete his half-realized conquest of a devastated Europe, while Isaac Newton and Ben Franklin attempt to defend the Hapsburg Emperor from the Russians while also trying to figure out how to avoid a repeat of the catastrophe that destroyed London. The spiritual world of the malakhim which provides the engine for much of the mystical "science" begins to appear as a player in its own right, although the question of the nature of these spirits being good, evil or some combination thereof remains somewhat of a mystery. The interplay between the material and spiritual worlds is an interesting one, especially as it is revealed though the American Indian's story.

Characters: Keyes' portrayal of historical characters is generally in line with what history tells us of their personalities, but his use of them is entirely too heavy in my opinion. Ben Franklin meets Isaac Newton meets Charles of Sweden meets Edward Teach (Blackbeard) meets Cotton Mather... yes, the research is solid and whatever historical anomalies exist (e.g. Newton) are explained reasonably in the story, but I always find this sort of historical name dropping to be rather tiring. Also, Ben Franklin's transformation from notorious ladies man to infatuated rescuer of damsel in distress is a bizarre one, especially since the damsel in question is described as being beneath his standards in terms of physical beauty.

Creativity: The confluence of science and alchemic magic is an interesting one, particularly as it involves figures such as Isaac Newton who had a tendency to confuse the two. This is not the first time this has been done, but it is conceived in a convincing manner and may be the first time that such a novel does not involve John Dee. The portrayal of religion is more serious than with most fantasy, and indeed, I was surprised to see that Cotton Mather was more than just the stereotypical religious strawman. The treatment of the malakhim was intriguing, particularly the concept of the creature possessing one of the secondary characters who, at first glance, appears to be quite human.

Text Sample: The emperor nodded at Newton and cleared his throat. "How fare things scientific, Sir Newton? Have you discovered anything of gravity?"

Ben chuckled aloud, but he was the only one in the room who did so. No one ever dared to laugh at the emperor's jokes, probably because the emperor himself never even twitched a smile. "A very clever pun, Your Majesty," he said, bowing once more. The emperor inclined his head toward Ben, then returned his attention to Sir Isaac. A few belated and forced titters drifted about the room, acocmpanied by additional venomous glances directed at Ben.

"Indeed, Sire," said Newton, "I have been making great strides of late in the development of a new system, one which, by comparison, shall make even my Principia appear rather pale."